Search

Article

x
中国物理学会期刊
Chinese Physics Letters Chinese Physics B 物理学报 物理 中国物理学会期刊网
Advance Search

留言板

尊敬的读者、作者、审稿人, 关于本刊的投稿、审稿、编辑和出版的任何问题, 您可以本页添加留言。我们将尽快给您答复。谢谢您的支持!

姓名
邮箱
手机号码
标题
留言内容
验证码

Novel two-dimensional materials and their heterostructures constructed in ultra-high vacuum

Li Geng ,  Guo Hui ,  Gao Hong-Jun

downloadPDF
Li Geng, Guo Hui, Gao Hong-Jun. Novel two-dimensional materials and their heterostructures constructed in ultra-high vacuum. Acta Phys. Sin., 2022, 71(10): 106801. doi: 10.7498/aps.71.20212407
Citation: Li Geng, Guo Hui, Gao Hong-Jun. Novel two-dimensional materials and their heterostructures constructed in ultra-high vacuum. Acta Phys. Sin., 2022, 71(10): 106801. doi: 10.7498/aps.71.20212407
shu
Next Previous

Novel two-dimensional materials and their heterostructures constructed in ultra-high vacuum

Li Geng, Guo Hui, Gao Hong-Jun
Acta Phys. Sin., 2022, 71(10): 106801.
doi: 10.7498/aps.71.20212407
Article Text (iFLYTEK Translation)
PDF
HTML
Get Citation

  • Abstract

    Compared with the three-dimensional bulk materials, two-dimensional (2D) materials exhibit superior electronic, optical, thermal, and mechanical properties due to the reduced dimensionality. The quantum confinement effect of 2D materials gives rise to exotic physical properties, and receives extensive attention of the scientists. Lots of routes to fabricate the 2D materials have been proposed by the material scientists, including the traditional mechanical exfoliation, chemical vapor deposition, molecular beam epitaxy under ultra-high vacuum (UHV), and so on. Among them, fabricating materials under ultra-high vacuum has the advantages of constructing large-scale and high-quality samples, and is therefore widely adopted in the 2D material growth. In this paper, we review three different strategies of growing 2D materials under UHV conditions, including molecular beam epitaxy, graphene intercalation and manual manipulation by nano probes. We compare the advantages and drawbacks among those methods in creating 2D materials, and try to provide some guidance to the community, especially those who are new to the field.
      PACS:
      68.37.-d(Microscopy of surfaces, interfaces, and thin films)
      68.37.Ef(Scanning tunneling microscopy (including chemistry induced with STM))
      81.15.Hi(Molecular, atomic, ion, and chemical beam epitaxy)
      61.48.Gh(Structure of graphene)

    Authors and contacts

    • 1.

      Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China

    • 2.

      School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China

    • 3.

      Songshan Lake Materials Laboratory, Dongguan 523808, PR China

      • Corresponding author: Gao Hong-Jun, hjgao@iphy.ac.cn
    • Funds: Project supported by the National Basic Research Program of China (Grant Nos. 2019YFA0308500, 2018YFA0305700), the National Natural Science Foundation of China (Grant Nos. 61888102, 51991340, 52072401), and the CAS Project for Young Scientists in Basic Research (Grant No. YSBR-003).

    FullText HTML

    2004年, 英国曼彻斯特大学的科学家Andre Geim和Kostya Novoselov将层状块体材料石墨通过机械解理的方法剥离成了单层的石墨烯, 首次敲开了二维材料研究的大门[1,2]. 二维材料的厚度仅为一层或几层原子, 这种独特的结构特征使得二维材料中的载流子表现出极强的二维限域性, 从而展现出一系列块体三维材料所不具备的物理化学性质, 引起了研究人员的广泛兴趣. 在过去的十多年间, 二维材料研究经历了井喷式的发展[3-5]. 到目前为止, 二维材料已经成为了一个庞大的学科, 其涉及的领域已经从单纯的材料科学拓展到物理、化学、信息、能源科学、生命科学乃至工业生产等. 可以预见, 在不久的将来, 二维材料可能会以不同的面目进入到人们的日常生活.

    对于一类有广阔应用前景的材料而言, 我们在惊叹于其优异的物理化学性能的同时, 更加需要关注它的制备方法. 正如高质量、易掺杂的单晶硅对于当今信息科学领域的重要性一样, 如何制备出高质量的二维原子晶体材料是这个领域发展的根基所在. 经历了十多年的发展, 材料学家们已经探索出了制备二维材料的多条道路, 包括机械解理、化学气相沉积、液相合成以及超高真空分子束外延等. 其中, 在超高真空环境下制备的二维材料具有清洁、大面积、高质量等一系列优势, 受到了研究人员的重视.

    本文将围绕二维原子晶体材料的超高真空原位制备, 回顾相关的研究工作, 同时梳理这个领域的发展. 将从三大类基于超高真空的新型二维材料构筑方法进行综述, 包括利用分子束外延构筑新型二维材料、利用石墨烯插层构筑新型二维原子晶体材料异质结构以及利用扫描探针原位操纵构筑二维材料复合结构. 通过比较三类方式各自的优势与局限, 对未来进行相关科研工作的人员提供有价值的参考意见.

    2.1   石墨烯以外的新型二维单元原子晶体材料

    2.1.1   硅烯的分子束外延生长

    在元素周期表中, 硅与碳属于同一主族, 因此具有类似的价电子结构. 当石墨烯作为二维材料被成功制备之后, 人们很自然地就想到了是否可以制备硅的二维材料, 即“硅烯”(silicene). 关于硅烯最早的研究是Takeda和hiraishi[6]在1994年的一项理论工作, Guzman-Verri和Voon[7]在2007年回顾这项工作时首次提出“硅烯”一词. 在理论预言中, 硅烯具有翘曲(buckled)结构. 相比于石墨烯而言, 硅原子具有更高的原子序数, 因而硅烯具有更强的自旋轨道耦合(spin-orbit coupling, SOC), 是研究量子自旋霍尔效应(quantum spin Hall effect)的良好体系[8,9].

    然而, 实验上, 硅烯的制备并没有显得那么的顺理成章. 与碳材料相比, 硅材料的最大不同是自然界中不具有类似石墨结构的层状硅材料. 具体而言, 自然界中的硅原子倾向于形成sp3杂化的金刚石结构, 而不喜欢形成sp2杂化的石墨结构. 这一特点的直接后果是在石墨烯制备中简单有效的机械剥离的方法失去了用武之地, 而人们也开始将目光转向了另一种制备方法-分子束外延. 2010年, Lalmi等[10]首次在Ag(111)表面尝试外延生长硅烯, 并且利用扫描隧道显微镜(scanning tunneling microscope, STM)观测到蜂窝状的结构. 然而, 他们观测到的蜂窝状结构的晶格常数相比块体材料中的Si—Si键长小了17%, 引起了同行的争议. 2012年, Vogt等[11]利用分子束外延在Ag(111)表面制备了硅烯, 并结合STM、角分辨光电子能谱(angle-resolved photoemission spectroscopy, ARPES)以及第一性原理计算首次给出了外延硅烯的确凿实验证据, 如图1(a)所示. 很快, Ag(111)表面外延生长硅烯的结果被多个课题组重复[12,13], 并且观察到了不同的相. 值得一提的是, 由于外延生长硅烯的翘曲结构, STM图像通常只能分辨出硅六元环中的三个硅原子. Onoda等[14]在2017年利用高分辨原子力显微镜(atomic force microscope, AFM)直接观测到了硅六元环, 证实了硅烯的二维蜂窝状结构.

    图 1 不同基底表面硅烯的分子束外延生长 硅烯在Ag(111)[11]　(a) ZrB2(0001)[17] (b) Ir(111)[18] (c) 和Ru(0001)[19] (d)表面生长的STM图像\r\nFig. 1. Molecular beam epitaxial growth of silicene monolayers on different substrates: STM images of silicene monolayer on Ag(111)[11] (a) ZrB2(0001)[17] (b) Ir(111)[18] (c) and Ru(0001)[19] (d), respectively.
    图 1  不同基底表面硅烯的分子束外延生长 硅烯在Ag(111)[11]　(a) ZrB2(0001)[17] (b) Ir(111)[18] (c) 和Ru(0001)[19] (d)表面生长的STM图像
    Fig. 1.  Molecular beam epitaxial growth of silicene monolayers on different substrates: STM images of silicene monolayer on Ag(111)[11] (a) ZrB2(0001)[17] (b) Ir(111)[18] (c) and Ru(0001)[19] (d), respectively.
    下载: 全尺寸图片 幻灯片

    尽管硅烯在Ag(111)表面的外延生长得到了广泛的认可, 有关硅烯的电子结构, 尤其是ARPES数据中类似狄拉克锥的特征的起源, 一直存在争议[15,16]. 因此, 在其他金属或单晶表面构筑硅烯具有重要意义. Fleurence等[17]报道了在ZrB2(0001)表面外延生长硅烯, 如图1(b)所示. 他们发现硅烯的翘曲以及应力会改变硅烯的电子结构, 并在Г点打开能隙. Meng等[18]报道了在Ir(111)表面外延生长硅烯, 如图1(c)所示. 他们将硅原子沉积在Ir(111)表面, 并在400 ℃下退火30 min, 获得了单层硅烯. 低能电子衍射(low energy electron diffraction, LEED)斑点显示硅烯相对金属衬底形成了$ \sqrt{7}\times \sqrt{7} $的结构, STM图像显示硅烯表面具有0.6 Å的起伏, 说明Ir(111)表面外延生长的硅烯也具有翘曲结构. 他们进一步做了电子局域函数(electron-localization-function, ELF)的计算, 证实了硅烯中近邻硅原子之间存在共价键. Huang等[19]报道了在Ru(0001)表面外延生长硅烯. 通过改变硅原子在Ru(0001)基底表面的沉积量, 他们发现低覆盖度下硅原子形成鱼骨状的六元环结构, 这种结构在高覆盖度下逐步演化为翘曲的蜂窝状硅烯, 如图1(d)所示.

    在以上这些外延硅烯体系中, 硅烯均以翘曲结构存在, 硅原子采取混合型sp2/sp3杂化的方式成键. 这种成键方式离不开基底的支撑, 因此外延生长的硅烯无法像外延石墨烯一样可以利用化学转移的方法进行剥离. 此外, 硅烯相比石墨烯而言具有极大的化学活性, 非常容易和氧化性气体发生反应, 破坏其本征的晶体结构[20,21]. 如何获得自由状态的硅烯, 以及如何测得硅烯的本征物理性质, 成为了领域内的挑战与焦点. Du等[22]首先在Ag(111)上外延生长双层硅烯, 然后利用插层氧化的方式将靠近金属基底的一层硅烯氧化掉形成缓冲层. 利用这种方法, 他们获得了上层的准自由状态单层硅烯. Tao等[23]在银薄膜上生长硅烯, 并利用这层金属薄膜作为电极, 首次测得了硅烯在室温下的迁移率为100 cm2·V–1·s–1. 受到硅烯化学活性的影响, 这类器件在空气中仅能存活几分钟. 因此, 硅烯在未来是否可以用以构筑电子信息器件, 还有待材料学家们的进一步挖掘与探索.

    2.1.2   锗烯、锡烯和铅烯的分子束外延生长

    人们研究硅烯的初衷之一是它相比石墨烯具有更强的SOC, 一方面可能会诱导新物理现象, 如量子自旋霍尔效应, 另一方面会打开更大的能隙, 解决石墨烯零能隙器件无法调控的问题. 因此, 在研究硅烯的同时, 很自然就会联想到原子序数更大, SOC更强的IV族元素锗、锡和铅[8,9].

    Li等[24]报道了Pt(111)表面锗烯的外延生长. 他们将锗原子沉积到Pt(111)表面, 然后在600—750 K退火30 min, 得到单层锗烯. LEED和STM图像显示锗烯相对金属基底存在$ \sqrt{19}\times \sqrt{19} $的超结构(图2(a)), DFT计算显示锗烯也存在类似硅烯的翘曲结构(图2(b)). Qin等[25]报道了Cu(111)表面双层锗烯的外延生长, 如图2(c)和图2(d)所示. 靠近金属衬底的一层锗烯作为缓冲层, 将上层锗烯和金属衬底有效隔离. 他们利用扫描隧道谱在双层锗烯表面观测到V型的狄拉克锥结构, 证实上层锗烯为准自由状态. 此外, 锗烯在Ge2Pt[26], Au(111)[27], Al(111)[28], MoS2[29]和Ag(111)[30]等衬底上均被成功制备.

    图 2 (a), (b) 单层锗烯在Pt(111)表面外延生长的STM图像(a)和原子模型示意图(b)[24]; (c), (d) 双层锗烯在Cu(111)表面外延生长的STM图像(c)和原子模型示意图(d)[25]\r\nFig. 2. (a), (b) STM image (a) and atomic model (b) of germanene monolayer on Pt(111)[24]; (c), (d) STM image (c) and atomic model (d) of germanene bilayer on Cu(111)[25].
    图 2  (a), (b) 单层锗烯在Pt(111)表面外延生长的STM图像(a)和原子模型示意图(b)[24]; (c), (d) 双层锗烯在Cu(111)表面外延生长的STM图像(c)和原子模型示意图(d)[25]
    Fig. 2.  (a), (b) STM image (a) and atomic model (b) of germanene monolayer on Pt(111)[24]; (c), (d) STM image (c) and atomic model (d) of germanene bilayer on Cu(111)[25].
    下载: 全尺寸图片 幻灯片

    二维锡烯被理论预言是一种拓扑绝缘体材料[31]. 实验上锡烯最早是2015年由Zhu等[32]在Bi2Te3(111)表面利用分子束外延的方式制备得到. 他们在室温下将锡原子沉积到Bi2Te3(111)衬底表面形成锡烯, 利用低温STM确定了锡烯的原子结构(图3(a)), 并结合ARPES和DFT计算证实这种材料是具有较大能隙的拓扑绝缘体. 随后, Xu等[33]、Zang等[34]和Xu等[35]报道了在InSb(111)表面的Sb终止面上外延生长锡烯, 并成功得到了灰锡和α-Sn两种不同的相. 他们利用ARPES证实了灰锡相具有0.44 eV的带隙[33], 如图3(b)所示, 而α-Sn能带结构具有拓扑狄拉克半金属特征[35]. Zheng等[36]也报道了多层锡烯在InSb(111)表面的生长. 他们发现单层锡烯具有约0.2 eV的能隙, 这个能隙随着层数增多而显著减小, 最终达到块体材料的狄拉克半金属态. 在能带变化的过程中伴随着拓扑相变[36].

    图 3 锡烯在不同衬底上的分子束外延生长　(a) 单层锡烯在Bi2Te3(111)表面外延生长的STM图像[32]; (b) InSb(111)表面外延生长锡烯和钾掺杂锡烯在Г点附近的能带结构[33]; (c), (d) Cu(111)表面外延生长纯平锡烯的大面积STM图像(c)和原子分辨图像(d)[37]; (e) Ir(111)上外延氮化硼表面生长锡烯的STM图像[40]\r\nFig. 3. Molecular beam epitaxial growth of stanene monolayers on different substrates: (a) STM image of buckled stanene on Bi2Te3(111)[32]; (b) band structure of as-grown and K doped stanene on InSb(111)[33]; (c), (d) large-scale (c) and atomically-resolved (d) STM images of flat stanene on Cu(111)[37]; (e) STM image of stanene on BN/Ir(111)[40].
    图 3  锡烯在不同衬底上的分子束外延生长　(a) 单层锡烯在Bi2Te3(111)表面外延生长的STM图像[32]; (b) InSb(111)表面外延生长锡烯和钾掺杂锡烯在Г点附近的能带结构[33]; (c), (d) Cu(111)表面外延生长纯平锡烯的大面积STM图像(c)和原子分辨图像(d)[37]; (e) Ir(111)上外延氮化硼表面生长锡烯的STM图像[40]
    Fig. 3.  Molecular beam epitaxial growth of stanene monolayers on different substrates: (a) STM image of buckled stanene on Bi2Te3(111)[32]; (b) band structure of as-grown and K doped stanene on InSb(111)[33]; (c), (d) large-scale (c) and atomically-resolved (d) STM images of flat stanene on Cu(111)[37]; (e) STM image of stanene on BN/Ir(111)[40].
    下载: 全尺寸图片 幻灯片

    在Bi2Te3(111)与InSb(111)表面生长的锡烯均具有翘曲结构, 与硅烯和锗烯类似. 2018年Deng等[37]在Cu(111)表面实现了纯平的锡烯生长(图3(c)和图3(d)), 并观测到了拓扑能带反转. 同年Yuhara等[38,39]也在Ag(111)表面得到了纯平的锡烯. 值得一提的是, 以上的工作中锡烯的生长都是直接在金属衬底之上. 与硅烯、锗烯类似, 金属基底与二维材料的相互作用较强, 尤其是这类翘曲的需要衬底支持的二维材料体系. 减弱这种相互作用, 获得更加自由、电子结构更加本征的锡烯, 需要将锡烯生长在绝缘衬底上或是在锡烯和金属衬底之间引入缓冲层. 近期, Dong等[40]利用Ir(111)表面生长的单层氮化硼作为衬底(图3(e)), 成功实现了近自由状态的锡烯生长.

    作为最重的IV族元素, 二维的铅烯也受到了研究人员的广泛关注. 第一性原理计算预言自由状态的单层铅烯是一种有很大能隙的半导体材料, 在电子掺杂下可以成为拓扑绝缘体[41,42], 并且还是一种实现室温量子自旋霍尔效应的理想材料[43]. 更为重要的是, 计算预言翘曲结构的铅烯有着很好的热力学稳定性[44], 有望在实验中制备得到. 实验上对二维的铅膜的研究由来已久. 利用分子束外延技术, 单层或多层的二维铅薄膜可以生长在Si(111)等衬底上, 并且展示出了独特的量子限域效应[45]和超导特性[46-48]等. 然而, 在Si(111)表面生长的铅膜并不具有蜂窝状结构[46], 而是作为顶戴原子选择性吸附于Si(111)表面特定位点. 同时, 铅元素也很容易与其他金属元素形成合金相, 不利于铅烯的制备. 因此, 选择合适的生长基底与生长方案对铅烯的制备尤为重要.

    2019年, Yuhara等[49]首次在Pd(111)表面成功制备了单层铅烯. 他们首先在干净的Pd(111)表面沉积铅原子, 高温退火(550 ℃)后可以在Pd晶体表面形成一层Pd1–xPbx(111)合金相薄膜. 接下来, 他们同样利用高温退火的方法, 让铅原子从合金相薄膜中偏析到晶体表面, 形成铅烯(图4(a)). 这一过程有别于传统的分子束外延生长方法, 与碳原子在高温下从Ru, Rh等晶体内部偏析到晶体表面形成石墨烯类似. 他们利用STM直接观察到了铅烯的纯平蜂窝状原子结构(图4(b)). 需要指出的是, 因为偏析的温度与形成合金的退火温度相同(550 ℃), 铅烯与合金相薄膜的形成是同步出现的. 为了证实偏析过程的存在, 他们利用离子溅射的方式除去了表面的铅烯, 然后重新退火之后再次得到了新的从合金相偏析到表面的铅烯. 在他们的工作之后, Bihlmayer等[50]也在Ir(111)表面的单层Fe薄膜上制备得到了纯平蜂窝状结构的铅烯.

    图 4 铅烯在不同衬底上的分子束外延生长 (a), (b) 单层铅烯在Pd(111)表面外延生长的大面积(a)和原子分辨(b) STM图像[49]; (c), (d) 单层铅烯在Fe/Ir(111)表面外延生长的原子分辨STM图像(c)和原子结构模型(d)[50]; (e) 单层铅烯在Fe/Ir(111)表面外延生长的大面积STM图像[50]\r\nFig. 4. Molecular beam epitaxial growth of plumbene monolayers on different substrates: (a), (b) Large-scale (a) and atomically-resolved (b) STM image of planar plumbene on Pd(111)[49];(c), (d) atomically-resolved STM image (c) and atomic model of plumbene on monolayer Fe on Ir(111)[50]; (e) large-scale STM image of planar plumbene on monolayer Fe on Ir(111)[50].
    图 4  铅烯在不同衬底上的分子束外延生长 (a), (b) 单层铅烯在Pd(111)表面外延生长的大面积(a)和原子分辨(b) STM图像[49]; (c), (d) 单层铅烯在Fe/Ir(111)表面外延生长的原子分辨STM图像(c)和原子结构模型(d)[50]; (e) 单层铅烯在Fe/Ir(111)表面外延生长的大面积STM图像[50]
    Fig. 4.  Molecular beam epitaxial growth of plumbene monolayers on different substrates: (a), (b) Large-scale (a) and atomically-resolved (b) STM image of planar plumbene on Pd(111)[49];(c), (d) atomically-resolved STM image (c) and atomic model of plumbene on monolayer Fe on Ir(111)[50]; (e) large-scale STM image of planar plumbene on monolayer Fe on Ir(111)[50].
    下载: 全尺寸图片 幻灯片

    对于锗烯、锡烯和铅烯而言, 它们更大的SOC可能会引起更多的新奇物理效应, 从基础研究的角度来看, 构筑不同结构、不同应力以至于不同相的锗烯和锡烯二维材料并探索它们的新奇物性具有很大的意义. 从应用前景来看, 与硅烯类似, 它们也都存在着无法剥离以及化学活性较高的问题. 如何克服这些问题, 将锗烯和锡烯的优良物性真正应用起来, 还有较长的路需要探索.

    2.1.3   其他III、V族元素的二维原子晶体材料

    除了IV族元素, III和V族元素的原子晶体也受到了广泛关注. 其中III族的硼元素可以在金属衬底表面外延生长形成二维硼烯. 2013年, 有多个研究组理论预言了硼烯材料的存在[51,52]. 由于硼元素的sp2电子结构和较短的共价键, 使得硼烯容易形成多种不同的构型. 有趣的是, 硼单质是半导体材料, 但是当材料从三维降为二维时, 硼烯被预言具有金属性. 2015年, Mannix等[53]在银单晶表面生长得到了单原子层的硼烯材料, 并通过STM等表征手段, 研究了该材料的各项异性与金属性, 与理论预言一致(图5(a)和图5(b)). 随后Feng等[54]又报道了在银单晶表面制备生长另外两种(β12和χ3)构型的单层硼烯材料(图5(c)和图5(d)). 这两种硼烯都具有三角形晶格结构, 但是具有不同的周期性空穴排列规律. 2021年, 两个研究组又报道了两种不同的双层硼烯结构[55,56], 分别是在铜单晶表面生长的类似β12结构的双层硼烯(图5(e)和图5(f))和在银表面生长的类似α结构的双层硼烯(图5(g)和图5(h)), 两种双层硼烯材料都具有很强的层间相互作用.

    图 5 单层和双层硼烯的分子束外延生长 (a)—(d) 单层硼烯在Ag(111)表面外延生长的STM图像[53,54]; (e), (f) 双层硼烯在Cu(111)表面外延生长的STM图像[55]; (g), (h) 双层硼烯在Ag(111)表面外延生长的STM图像[56]\r\nFig. 5. Molecular beam epitaxial growth of borophene monolayers and bilayers: (a)–(d) STM images of monolayer borophene on Ag(111)[53,54]; (e), (f) STM images of bilayer borophene on Cu(111)[55]; (g), (h) STM images of bilayer borophene on Ag(111)[56].
    图 5  单层和双层硼烯的分子束外延生长 (a)—(d) 单层硼烯在Ag(111)表面外延生长的STM图像[53,54]; (e), (f) 双层硼烯在Cu(111)表面外延生长的STM图像[55]; (g), (h) 双层硼烯在Ag(111)表面外延生长的STM图像[56]
    Fig. 5.  Molecular beam epitaxial growth of borophene monolayers and bilayers: (a)–(d) STM images of monolayer borophene on Ag(111)[53,54]; (e), (f) STM images of bilayer borophene on Cu(111)[55]; (g), (h) STM images of bilayer borophene on Ag(111)[56].
    下载: 全尺寸图片 幻灯片

    V族元素的二维原子晶体也陆续被成功制备. 除了人们熟知的黑磷结构[57-59], 人们还预言并成功制备了单层的蓝磷结构[60,61] (图6(a)和图6(b)). 蓝磷是一种新的磷元素二维晶体结构, 与黑磷一样有清晰的层状结构且具有很高的稳定性. 通过扫描隧道谱研究金单晶表面的蓝磷结构, 发现其具有1.10 eV的电子能隙. 与蓝磷结构相似, V族的砷、锑元素也都存在这种褶皱的β相单层及多层结构, 称为砷烯、锑烯. 2017年, Wu等[62]报道了在PdTe2表面制备该结构的单层锑烯材料(图6(c)和图6(d)), 并发现了其较强的空气稳定性. Zhu等[63]报道了在铜表面外延生长的单层锑烯材料, 并研究了该材料的拓扑能带结构(图6(e)). 在单层锑烯之上进一步构筑锑烯的纳米岛结构远离了铜基底的电子态影响, 使纳米岛呈现出类似自由状态锑烯的电学性质. 通过扫描隧道显微镜研究纳米岛的局域电子态密度, 观察到了清晰的一维拓扑边界态(图6(f)), 并且该边界态与体相能态来自于不同的能带, 该实验观测得到了DFT理论计算支持. 除此之外, Shao等[64]还报道了银单晶表面生长的纯平锑烯结构. 由于较强的面内拉应力, 使得银表面的锑原子由sp3杂化转变为sp2杂化, 锑烯结构也从褶皱结构转变为了蜂窝状结构. 2017年, Reis等[65]报道了在SiC表面生长的单层铋烯材料(图6(g)和图6(h)). 该材料具有平面结构, 表面呈现蜂窝状晶格. 通过AREPS以及STM等表征手段, 证实了其具有拓扑能带以及拓扑边界态.

    图 6 (a), (b) 单层蓝磷在Au(111)表面外延生长的STM图像(a)和原子模型示意图(b)[60]; (c), (d)单层锑烯在PdTe2表面外延生长的STM图像(c)和原子模型示意图(d)[62]; (e) 锑烯单层岛在Cu(111)表面外延生长的STM图像; (f) 跨过锑烯单层岛的扫描隧道谱[63]; (g), (h) 单层铋烯在SiC表面外延生长的STM图像(g)和原子模型示意图(h)[65]\r\nFig. 6. (a), (b) STM image (a) and atomic model (b) of monolayer blue phosphorus on Au(111)[60]; (c), (d) STM image (c) and atomic model (d) of monolayer antimonene on PdTe2[62]; (e) STM image of monolayer antimonene on Cu(111); (f) Waterfall-like dI/dV spectra along the arrow in Fig. (e)[63]; (g), (h) STM image (g) and atomic model (h) of monolayer bismuthene on SiC[65].
    图 6  (a), (b) 单层蓝磷在Au(111)表面外延生长的STM图像(a)和原子模型示意图(b)[60]; (c), (d)单层锑烯在PdTe2表面外延生长的STM图像(c)和原子模型示意图(d)[62]; (e) 锑烯单层岛在Cu(111)表面外延生长的STM图像; (f) 跨过锑烯单层岛的扫描隧道谱[63]; (g), (h) 单层铋烯在SiC表面外延生长的STM图像(g)和原子模型示意图(h)[65]
    Fig. 6.  (a), (b) STM image (a) and atomic model (b) of monolayer blue phosphorus on Au(111)[60]; (c), (d) STM image (c) and atomic model (d) of monolayer antimonene on PdTe2[62]; (e) STM image of monolayer antimonene on Cu(111); (f) Waterfall-like dI/dV spectra along the arrow in Fig. (e)[63]; (g), (h) STM image (g) and atomic model (h) of monolayer bismuthene on SiC[65].
    下载: 全尺寸图片 幻灯片

    在非金属元素以外, Li等[66]还实现了过渡金属铪的二维原子晶体材料生长, 即铪烯, 如图7所示. 他们在Ir(111)单晶表面沉积铪原子, 退火之后用STM观测到了蜂窝状网格结构. 结合第一性原理计算, 他们确定这个结构来源于蜂窝状排列的铪原子. 这也是实验上首次观测到过渡金属的二维蜂窝状材料.

    图 7 (a) Ir(111)表面大面积单层铪的STM图像; (b) 原子分辨的单层铪STM图像; (c) 铪烯的STM图像、STM模拟图像以及原子结构示意图[66]\r\nFig. 7. (a) Large-scale STM image of monolayer Hf on Ir(111); (b) Atomically-resolved STM image of monolayer Hf on Ir(111); (c) The STM image, simulated STM image, and atomic model of a Hafnene monolayer on Ir(111), showing honeycomb Hf lattice[66].
    图 7  (a) Ir(111)表面大面积单层铪的STM图像; (b) 原子分辨的单层铪STM图像; (c) 铪烯的STM图像、STM模拟图像以及原子结构示意图[66]
    Fig. 7.  (a) Large-scale STM image of monolayer Hf on Ir(111); (b) Atomically-resolved STM image of monolayer Hf on Ir(111); (c) The STM image, simulated STM image, and atomic model of a Hafnene monolayer on Ir(111), showing honeycomb Hf lattice[66].
    下载: 全尺寸图片 幻灯片

    2.2   新型二维双元及多元原子晶体材料

    利用分子束外延技术, 人们还可以构筑二维双元原子晶体材料以及二维分子晶体材料[67-76]等. Lu等[77,78]通过分子束外延的方法在Au(111)单晶表面可控制备了高质量规则边界形状的单层2H-MoSe2二维材料. 他们发现单层2H-MoSe2岛具有两种规则的边界构型: 其中短边为裸露的硒边界, 长边为单个硒原子饱和的钼边, 如图8所示. 这种超高真空内可控制备的TMD二维材料充分暴露了钼原子截止的边界, 可用于提高基于TMDs材料的光催化和电催化效率. 金属表面构筑双元原子晶体材料的优势在于金属的催化性能. 然而, 金属基底与二维材料之间的相互作用会很大程度影响和改变二维材料的性能. 例如, Kezilebieke等[79]在NbSe2表面外延生长磁性的二维CrBr3材料. NbSe2的超导电性近邻到CrBr3纳米岛, 使得它的能带出现拓扑超导特性. 他们进一步在纳米岛边界观测到了一维的马约拉纳边界态.

    图 8 (a) Au(111)表面单层MoSe2岛的STM图像; (b) MoSe2岛的原子分辨STM图像; (c), (d) 大面积(c)和原子分辨(d)的Mo边界STM图像; (e) MoSe2上不同区域的dI/dV谱线; (f) MoSe2岛边界上不同位置的dI/dV谱线[77]\r\nFig. 8. (a) STM image of monolayer MoSe2 islands on Au(111) substrate; (b) atomic-resolved STM image of single-layer MoSe2 with hexagonal lattice; (c), (d) large-scale (c) and atomically resolved (d) STM image of Mo edge; (e) normalized dI/dV curves obtained on the three different domains of MoSe2 on Au(111); (f) Six normalized dI/dV curves taken on the six edges of one MoSe2 island[77].
    图 8  (a) Au(111)表面单层MoSe2岛的STM图像; (b) MoSe2岛的原子分辨STM图像; (c), (d) 大面积(c)和原子分辨(d)的Mo边界STM图像; (e) MoSe2上不同区域的dI/dV谱线; (f) MoSe2岛边界上不同位置的dI/dV谱线[77]
    Fig. 8.  (a) STM image of monolayer MoSe2 islands on Au(111) substrate; (b) atomic-resolved STM image of single-layer MoSe2 with hexagonal lattice; (c), (d) large-scale (c) and atomically resolved (d) STM image of Mo edge; (e) normalized dI/dV curves obtained on the three different domains of MoSe2 on Au(111); (f) Six normalized dI/dV curves taken on the six edges of one MoSe2 island[77].
    下载: 全尺寸图片 幻灯片

    研究二维材料的本征物理化学性质, 需要将它们与金属衬底有效隔绝. 石墨烯化的碳化硅衬底常被用做生长基底, 用于包括PdTe2, MoSe2, PdSe2等的二维材料生长[80-84]. 在这种衬底上生长出来的二维材料与石墨烯之间是范德瓦耳斯堆叠, 从而可以保持本征的物性. 在生长二维材料之前, SiC(1000)衬底通常会被闪火至1500 K左右, 这种处理方式会在衬底上形成单层或双层石墨烯的原子级平整的表面. 图9(a)和图9(b)分别是碳化硅衬底上双层石墨烯上通过分子束外延生长的多层PdTe2[80]和单层MoSe2[81]. 角分辨光电子能谱研究显示PdTe2的能带具有拓扑非平庸特征, 而光致发光谱研究表明MoSe2双粒子跃迁性质. 值得注意的是, 碳化硅上的石墨烯对二维材料会有电子掺杂的效果. Li等[82]报道了利用分子束外延方式生长的双层PdSe2. 当双层PdSe2跨过单层和双层石墨烯时, 可以看到不同程度的电子掺杂效果, 如图9(d)所示. 从图9(d)可以看到, 无论是单层还是双层石墨烯的碳化硅基底, 对双层PdSe2都具有很强的电子掺杂效果. 从实验结果看, 增加石墨烯的层数会降低衬底对材料的掺杂程度. 图9(d)跨过BLG/SiC和MLG/SiC基底连续生长的PdSe2上测得的扫描隧道谱, 可以看到, BLG/SiC基底对PdSe2的电子掺杂程度弱于MLG/SiC基底. 测量结果显示, 在不同基底上, 能带整体位移达到0.2 eV. Fan等[83]对PdSe2在真空中低于生长温度的条件下退火半小时左右, 由于缺硒的生长条件, 得到Pd2Se3, 如图9(e)所示. 他们通过扫描隧道谱的表征发现Pd2Se3的能隙是层数依赖的. 跨过单层和双层Pd2Se3测得的一系列谱线(图9(f))显示单层Pd2Se3比双层Pd2Se3的能隙大0.1 eV左右[84]. 由于不同层数能隙大小的不同, 单层Pd2Se3和双层Pd2Se3之间形成了电子态层面的异质结. 在双层Pd2Se3的边界处出现了p型能带弯曲. 上述结果显示, 在石墨烯化的碳化硅上生长二维材料是十分有效的手段. 相对于金属衬底, 石墨烯化碳化硅衬底与二维材料之间的范德瓦耳斯弱耦合更有利于我们对材料本征性质进行研究. 并且, 可以通过控制碳化硅上石墨烯的层数来实现对二维材料不同程度的掺杂, 调节材料的电子和光电性质, 甚至构筑p-n结.

    图 9 (a) 双层石墨烯/碳化硅衬底上生长的大面积多层PdTe2[80]; (b) 双层石墨烯/碳化硅衬底上生长的单层MoSe2[81]; (c) 石墨烯化碳化硅衬底上生长的PdSe2; (d) 在跨过单层和双层石墨烯/碳化硅衬底上连续生长的双层PdSe2上测得的扫描隧道谱[82]; (e) 石墨烯化碳化硅衬底上生长的Pd2Se3[83]; (f) 跨过单层和双层Pd2Se3台阶测得的扫描隧道谱[84]\r\nFig. 9. (a) Multi-layer PdTe2 on bilayer graphene on SiC substrate[80]; (b) monolayer MoSe2 on bilayer graphene on SiC substrate[81]; (c) bilayer PdSe2 on bilayer graphene on SiC substrate; (d) dI/dV spectra taken on bilayer PdSe2 on top of mono- and bi- layer graphene substrate[82]; (e) Pd2Se3 on bilayer graphene on SiC substrate[83]; (d) dI/dV spectra taken across mono- and bi- layer Pd2Se3[84]
    图 9  (a) 双层石墨烯/碳化硅衬底上生长的大面积多层PdTe2[80]; (b) 双层石墨烯/碳化硅衬底上生长的单层MoSe2[81]; (c) 石墨烯化碳化硅衬底上生长的PdSe2; (d) 在跨过单层和双层石墨烯/碳化硅衬底上连续生长的双层PdSe2上测得的扫描隧道谱[82]; (e) 石墨烯化碳化硅衬底上生长的Pd2Se3[83]; (f) 跨过单层和双层Pd2Se3台阶测得的扫描隧道谱[84]
    Fig. 9.  (a) Multi-layer PdTe2 on bilayer graphene on SiC substrate[80]; (b) monolayer MoSe2 on bilayer graphene on SiC substrate[81]; (c) bilayer PdSe2 on bilayer graphene on SiC substrate; (d) dI/dV spectra taken on bilayer PdSe2 on top of mono- and bi- layer graphene substrate[82]; (e) Pd2Se3 on bilayer graphene on SiC substrate[83]; (d) dI/dV spectra taken across mono- and bi- layer Pd2Se3[84]
    下载: 全尺寸图片 幻灯片

    除了分子束外延技术以外, 二维双元原子晶体材料还可以通过表面化学反应在金属单晶表面直接制备[74,85-91]. Wang等[85]利用金属表面硒化的方法在Pt(111)表面构筑了单层的PtSe2. 他们利用ARPES证实了单层PtSe2的半导体特征, 并证实了其光催化活性. Lin等[87]进一步利用这种技术构筑了两种 “自然图案化”材料: 具有交替三角形拼图图案的1H/1T型单层二硒化铂(1H/1T-PtSe2)(图10(a)和图10(b))以及具有周期排列三角孔洞的单层硒化铜(CuSe)(图10(c)—(g)). 这两种新型二维双元原子晶体材料均具有选择性功能化的特征, 可以选择性的吸附有机分子或金属原子. 此外, 它们在空气中也有很好的稳定性, 具有潜在的应用前景.

    图 10 (a), (b) 1T/1H相的PtSe2三角图案的结构示意图与STM图像[87]; (c), (d) Cu(111)表面CuSe的周期性三角孔洞结构[87]; (e)—(g) CuSe的扫描透射电镜图像、电镜模拟图像以及原子结构示意图[87]\r\nFig. 10. (a), (b) The schematic and STM image of the triangular pattern of 1T/1H phase PtSe2 on Pt(111)[87]; (c), (d) large-scale and zoom-in STM images of the periodic triangle holes in CuSe monolayer[87]; (e)–(g) scanning transmission electron microscopy image, the simulated image and atomic model of monolayer CuSe on Cu(111)[87].
    图 10  (a), (b) 1T/1H相的PtSe2三角图案的结构示意图与STM图像[87]; (c), (d) Cu(111)表面CuSe的周期性三角孔洞结构[87]; (e)—(g) CuSe的扫描透射电镜图像、电镜模拟图像以及原子结构示意图[87]
    Fig. 10.  (a), (b) The schematic and STM image of the triangular pattern of 1T/1H phase PtSe2 on Pt(111)[87]; (c), (d) large-scale and zoom-in STM images of the periodic triangle holes in CuSe monolayer[87]; (e)–(g) scanning transmission electron microscopy image, the simulated image and atomic model of monolayer CuSe on Cu(111)[87].
    下载: 全尺寸图片 幻灯片

    利用金属表面硒化、碲化以及砷化的方法构筑的二维双元原子晶体材料还包括Cu2Se[91], AgTe[89], IrTe2[90]和AgAs[74]等. 这种方法相比于分子束外延更为简单, 但同时也受限于金属和非金属元素的选择.

    除二维双元原子晶体材料外, 分子束外延技术在制备高质量具有拓扑、磁性、超导等新奇物性的复杂二维材料体系方面也具有独特的优势. Li等[92]利用分子束外延技术在SrTiO3(111)表面制备出了厚度约为18 nm的磁性外尔半金属Co3Sn2S2薄膜. Gong等[93]通过交替生长Bi2Te3五重层和MnTe双层, 成功构筑了本征磁性拓扑绝缘体MnBi2Te4, 并利用ARPES进一步证实了其存在的Dirac表面态. Wang等[94]利用分子束外延技术在SrTiO3(001)表面成功制备了单个晶胞厚度的高温超导体FeSe, 超导转变温度为77 K. Chang等[95]报道了利用分子束外延方式生长的高质量、不同层厚的超导体LiFeAs薄膜. 此外, 在具有复杂组份的超导[96,97]、拓扑材料[98,99]及氧化物薄膜[100,101]制备方面, 分子束外延技术同样发挥着重要作用.

    外来的原子分子可以通过缺陷、褶皱、裂缝以及边界等位置穿过石墨烯, 达到石墨烯和外延衬底的界面, 形成新的二维结构, 这一过程被称作插层[102]. 插层现象在外延石墨烯体系中被大量的报道, 是一种非常普适的物理现象[5,102-120]. 在这一小节中, 将回顾利用石墨烯与外延衬底之间的这一天然二维界面构筑新型二维原子晶体材料的相关工作.

    3.1   石墨烯插层机制

    外延石墨烯的插层是一个普适的物理现象. 过去人们提出了多种物理机制来解释这一奇特的过程. 早期的低能电子显微镜(low-energy electron microscopy, LEEM)实验直接观测到了金属原子和小分子从石墨烯岛的边界开始扩散并实现插层的过程[111,119]. 此外, 石墨烯上本征存在的褶皱[112,117]和缺陷[120]等也可以促进插层过程的进行. 这类插层机制非常直观, 外来原子或分子从边界或缺陷处扩散达到石墨烯和衬底的界面的势垒较低, 因此插层过程容易进行.

    随着研究的进行, 人们发现在几乎没有缺陷的大面积外延石墨烯体系中[121,122], 插层过程依然可以进行[123]. 这些发现对以往的插层机制提出了挑战. 为了解决这一问题, Li等[105]系统地研究了硅原子在石墨烯/钌(0001)外延体系的插层问题. 他们首先将少量硅原子沉积在石墨烯表面, 退火到400 ℃, 发现石墨烯表面出现了许多原子量级大小的亮点. 高分辨的STM图像显示, 这些亮点是石墨烯中碳原子空位的缺陷. DFT计算表明, 吸附的硅原子和钌衬底的协同作用可以极大地降低碳原子空位缺陷的形成能, 从而在石墨烯表面诱导出大量缺陷. 这些缺陷出现的位置是随机的, 与实验观测到的硅原子插层的位置随机这一现象相符合.

    为了进一步证实这些诱导出的缺陷与硅原子插层过程相关, 他们利用低能氩离子轰击的办法直接在干净的石墨烯/钌(0001)表面构造出空位缺陷, 然后进行插硅实验. 实验结果显示, 在相同的硅原子沉积量下, 初始缺陷浓度越高, 硅插层的效率越高. 这一对比实验直接证实了硅原子通过碳空位缺陷进行扩散, 达到石墨烯/衬底界面. DFT计算也显示了单个硅原子通过碳空位进行扩散的势垒大大降低. 同时, 当硅原子扩散到界面后, 整个体系的能量也大大降低. 这一结果说明, 硅原子停留在石墨烯/钌界面比吸附于石墨烯表面更加的稳定, 一旦硅原子插层完成, 它就不太可能重新通过缺陷脱附. 最后, 钌晶体内溶解的碳原子可以在高温下偏析到晶体表面, 从而修复缺陷. 这一过程使得插层过后的石墨烯仍然具有很少的缺陷.

    基于以上实验现象和计算结果, Li等[105]提出了诱导缺陷、通过缺陷插层、界面原子扩散和缺陷修复的协同插层机制. 他们进一步从实验和计算两个方面证实了这一协同插层机制是一种普适的机制, 可以用于解释不同外延石墨烯体系中多种外来原子的插层过程.

    3.2   石墨烯/硅烯异质结构的构筑

    3.2.1   单层石墨烯/硅烯异质结构的构筑

    外延石墨烯的协同插层机制确保了插层过程中石墨烯不会受到破坏, 同时插层后的原子在石墨烯和衬底的界面由于空间受限效应会生长成为二维结构, 因而可以利用插层来构筑二维原子晶体材料的异质结构.

    Li等[107]利用这一方案在钌(0001)单晶表面成功地构筑了大面积、高质量的石墨烯/硅烯异质结构. 他们通过DFT计算发现插层的硅原子会优先停留在石墨烯摩尔斑点的atop位, 并且开始生长成为六元环结构. 利用高分辨STM他们直接地观测到了石墨烯摩尔斑点atop位下方的硅烯纳米片段(图11(a)). 进一步增加插层硅原子, 界面处的硅烯纳米片段会互相连接, 最终形成$ \sqrt{7}\times \sqrt{7} $的硅烯结构(图11(b)). 这一结构与钌表面直接外延生长得到的硅烯结构类似, 说明石墨烯与硅烯之间的相互作用较弱. DFT计算表明石墨烯和硅烯之间没有成键, 是范德瓦耳斯力相互作用(图11(c)). 他们进一步构造了垂直输运器件, 发现了石墨烯/硅烯异质结构的整流效应(图11(d)).

    图 11 (a) 插层硅烯纳米片段的STM图像[107]; (b) 插层单层硅烯的STM图像[107]; (c) 石墨烯/硅烯异质结构的电子局域函数计算[107]; (d) 石墨烯/硅烯异质结构的整流效应[107]\r\nFig. 11. (a) STM image of the intercalated silicene nano flakes[107]; (b) STM image of the intercalated silicene monolayer[107]; (c) electron localization function calculation of the graphene/silicene heterostructure[107]; (d) rectifying effect of the graphene/silicene heterostructure[107].
    图 11  (a) 插层硅烯纳米片段的STM图像[107]; (b) 插层单层硅烯的STM图像[107]; (c) 石墨烯/硅烯异质结构的电子局域函数计算[107]; (d) 石墨烯/硅烯异质结构的整流效应[107]
    Fig. 11.  (a) STM image of the intercalated silicene nano flakes[107]; (b) STM image of the intercalated silicene monolayer[107]; (c) electron localization function calculation of the graphene/silicene heterostructure[107]; (d) rectifying effect of the graphene/silicene heterostructure[107].
    下载: 全尺寸图片 幻灯片

    由于石墨烯插层的普适性, 这一技术可以用于构筑其他的二维材料与石墨烯的异质结构. 此外, 界面处的二维材料是受到表面石墨烯保护的, 这也很大程度上解决了硅烯材料无法在空气中存在的问题. 利用这种方法制备的异质结构可以在空气中稳定存在[107].

    3.2.2   双层石墨烯/硅烯异质结构的构筑

    和单层石墨烯相比, 双层石墨烯不仅继承了单层石墨烯的优异性质, 同时还具有其独特的新奇物性, 一直是二维材料领域中的研究热点之一. 双层石墨烯的物理性质受到两层石墨烯层间转角的调控, 比如魔角石墨烯可实现关联绝缘态、超导、量子反常霍尔效应等[124-126]. 其中, 具有AB堆垛结构的双层石墨烯在破坏反演对称性的情况下具有非零能隙, 为石墨烯在电子及光电子学器件方面的应用提供了更多的可能性. 在AB堆垛双层石墨烯中诱导打开能隙的方式有多种, 比如通过施加电场[127-130]、应力[131]、或在两层石墨烯表面吸附原子/分子[132-135]构建电势差等. 第一性原理计算表明, 将两种/多种不同的调控方式结合起来, 可实现更大能隙的打开[135]; 而且基于双层石墨烯的异质结构, 尤其是双层石墨烯/硅烯垂直异质结在高性能晶体管器件方面具有潜在的应用[136], 但在实验方面至今未见报道.

    Guo 等[137]基于超高真空分子束外延技术, 首先在Ru(0001)衬底表面实现了高质量、厘米尺寸、AB堆垛双层石墨烯单晶的可控生长; 在此基础上通过硅插层技术在双层石墨烯和Ru衬底的界面处实现了硅原子插层, 如图12(a)和图12(b)所示[138]. 原位LEED表征结果显示, 插层到界面处的硅原子形成了相对于Ru(0001)晶格的$ \sqrt{7}\times \sqrt{7} $超结构, 进一步预示着界面处的硅原子形成了硅烯(图12(c)和图12(d)). 结合STM图像的分析, 证明了双层石墨烯体系的硅烯插层(图12(e)和图12(f)), 而且硅烯插层后顶层的双层石墨烯起伏变弱. 此外, 通过Raman光谱的变化证实了双层石墨烯/硅烯异质结的成功构筑(图12(g)). 由于石墨烯和Ru基底间较强的相互作用, Ru表面的石墨烯的Raman振动特征受到极大的影响, 在Ru基底表面外延生长的双层石墨烯表现出单层石墨烯的振动特征. 然而, 当硅烯插层之后, 双层石墨烯原有的Raman振动模式恢复, 2D峰的半高宽大于52 cm–1, 并拟合为四个洛伦兹单峰(图12(h)), 表明双层石墨烯的AB堆垛特性. 此外, 硅烯插层之后, 顶层的双层石墨烯的G峰和2D峰都出现了较大的蓝移, 分别是~20 cm–1和~45 cm–1, 表明在双层石墨烯中存在一定程度的掺杂和应力作用.

    图 12 (a), (b) Ru(0001)表面双层石墨烯/硅烯异质结构筑示意图[138]; (c), (d) 分别是硅烯插层前后的LEED图像[138]; (e), (f) 分别是硅烯插层前后的STM图像[138]; (g) Ru(0001)表面硅烯插层前后的单层石墨烯及双层石墨烯的Raman光谱对比[138]; (h) 硅烯插层后双层石墨烯的2D特征峰的分析拟合[138]\r\nFig. 12. (a), (b) Schematic of the fabrication process of BLG/silicene heterostructure on Ru(0001)[138]; (c), (d) LEED patterns of BLG/Ru and BLG/silicene/Ru, respectively[138]; (e), (f) corresponding STM images for BLG/Ru and BLG/silicene/Ru, respectively[138]; (g) comparison of Raman spectra of SLG/Ru (black), SLG/silicene/Ru (green), BLG/Ru (red) and BLG/silicene/Ru (blue) [138]; (h) 2D band of BLG/silicene/Ru well fitted with four narrow Lorentzian components[138].
    图 12  (a), (b) Ru(0001)表面双层石墨烯/硅烯异质结构筑示意图[138]; (c), (d) 分别是硅烯插层前后的LEED图像[138]; (e), (f) 分别是硅烯插层前后的STM图像[138]; (g) Ru(0001)表面硅烯插层前后的单层石墨烯及双层石墨烯的Raman光谱对比[138]; (h) 硅烯插层后双层石墨烯的2D特征峰的分析拟合[138]
    Fig. 12.  (a), (b) Schematic of the fabrication process of BLG/silicene heterostructure on Ru(0001)[138]; (c), (d) LEED patterns of BLG/Ru and BLG/silicene/Ru, respectively[138]; (e), (f) corresponding STM images for BLG/Ru and BLG/silicene/Ru, respectively[138]; (g) comparison of Raman spectra of SLG/Ru (black), SLG/silicene/Ru (green), BLG/Ru (red) and BLG/silicene/Ru (blue) [138]; (h) 2D band of BLG/silicene/Ru well fitted with four narrow Lorentzian components[138].
    下载: 全尺寸图片 幻灯片

    他们进一步对双层石墨烯/硅烯异质结中双层石墨烯的电子结构进行了研究. 如图13所示, ARPES结果表明, 在沿着Γ-K-M方向的能量-动量色散关系中, 石墨烯的能带结构呈双抛物线形状, 且这两条π带劈裂间距大约是0.4 eV, 表明了AB堆垛的双层石墨烯结构特征. 此外, 双层石墨烯受到了大约0.12 eV的电子掺杂, 掺杂浓度大约为4.4 × 1012 cm–2. 更显著的是, 在K点处, 双层石墨烯打开了一个大约为0.2 eV的较大能隙. 为了理解这一较大能隙产生的内在机制, 结合第一性原理计算, 在同时考虑双层石墨烯中所受电子掺杂和应力双重效应时, 计算结果显示双层石墨烯打开了0.15 eV的能隙, 与实验结果高度吻合. 有趣的是, 计算结果表明, 如果分别施加与实验同等程度的电子掺杂(或应力)作用, 只能在AB堆垛双层石墨烯中诱导打开0.06 eV (或0.02 eV)的较小能隙; 而考虑在具有应力的双层石墨烯上同时进行电子掺杂时, 可以在低浓度掺杂下打开0.17 eV的能隙, 如图13(d)—(f)所示. 这一结果表明, 双层石墨烯中较大能隙的产生并不是由单纯应力与单纯掺杂分别引起的能隙的简单加和, 而是电子掺杂和压应力双重效应协同作用的结果. 该工作提供了一种利用多重效应调控石墨烯能带结构的新方法, 对双层石墨烯在器件方面的应用具有重要价值[138].

    图 13 (a) 硅烯插层之后的双层石墨烯的ARPES谱[138]; (b) 优化后的起伏双层石墨烯/硅烯/Ru的原子结构模型[138]; (c) 基于图(b)中结构模型计算的能带结构, 红点组成了投影到双层石墨烯上的能带结构[138]; (d) 仅考虑来自硅烯/Ru衬底的掺杂效应时双层石墨烯的能带结构[138]; (e) 仅考虑双层石墨烯起伏/应力情况下的能带结构[138]; (f) 同时考虑掺杂和起伏/应力时双层石墨烯的能带结构[138]\r\nFig. 13. (a) ARPES intensity map of the BLG after silicene intercalation[138]; (b) an optimized structure model of rippled BLG on Ru(0001) after silicene intercalation[138]; (c) calculated band structure based on the structure model in (b). The red dots are the band projected on the BLG[138]; (d) a structure model of flat BLG on silicene/Ru and the corresponding calculated band structure[138]; (e) a structure model of rippled BLG and the corresponding calculated band structure[138]; (f) a structure model of Li-doped rippled BLG and the calculated band structure[138].
    图 13  (a) 硅烯插层之后的双层石墨烯的ARPES谱[138]; (b) 优化后的起伏双层石墨烯/硅烯/Ru的原子结构模型[138]; (c) 基于图(b)中结构模型计算的能带结构, 红点组成了投影到双层石墨烯上的能带结构[138]; (d) 仅考虑来自硅烯/Ru衬底的掺杂效应时双层石墨烯的能带结构[138]; (e) 仅考虑双层石墨烯起伏/应力情况下的能带结构[138]; (f) 同时考虑掺杂和起伏/应力时双层石墨烯的能带结构[138]
    Fig. 13.  (a) ARPES intensity map of the BLG after silicene intercalation[138]; (b) an optimized structure model of rippled BLG on Ru(0001) after silicene intercalation[138]; (c) calculated band structure based on the structure model in (b). The red dots are the band projected on the BLG[138]; (d) a structure model of flat BLG on silicene/Ru and the corresponding calculated band structure[138]; (e) a structure model of rippled BLG and the corresponding calculated band structure[138]; (f) a structure model of Li-doped rippled BLG and the calculated band structure[138].
    下载: 全尺寸图片 幻灯片

    3.3   石墨烯/双元二维材料异质结构的构筑

    利用超高真空分子束外延技术在Ru(0001)金属衬底表面外延生长的石墨烯具有大面积、高质量、单晶等优异性质. 然而金属衬底的导电性极大地限制了所制备石墨烯的进一步应用. 为了充分实现进一步的应用, 首要任务是将所制备的高质量石墨烯转移至绝缘衬底之上. 然而, 为了避免常规转移过程可能会引起的石墨烯质量的退化或界面污染等问题, 发展超高真空原位的制备技术实现石墨烯与金属衬底间的绝缘是一项重要且富有挑战的课题. 而插层技术为实现高质量石墨烯从金属基底向绝缘衬底的“原位转移”提供了更多的可能性.

    如图14所示, Guo等[108]基于在Ru(0001)表面外延生长的高质量、厘米尺寸、石墨烯单晶发展了分步插层技术, 即: 1)通过分步实现硅原子和氧原子的插层, 在石墨烯和Ru基底的界面处实现硅和氧的充分化学反应, 继而实现二氧化硅薄膜的生长, 而且在一定的条件下, 界面处的SiO2可形成晶态双层结构; 2)通过进一步增加硅原子和氧原子的插层量, 使得界面处SiO2层逐渐变厚, 其结构也由晶态转变为非晶态. 最终, 当二氧化硅层到达一定厚度时, SiO2薄膜使石墨烯与金属衬底绝缘, 实现高质量外延石墨烯从金属衬底向绝缘二氧化硅衬底的“原位转移”, 从而可进一步实现外延石墨烯原位电子学器件的构筑. 利用LEED分别对不同阶段的材料样品进行表征, 其中界面处的薄层二氧化硅形成了相对于Ru(0001)基底的2 × 2有序结构, 而较厚的二氧化硅层则具有非晶态结构.

    图 14 Ru(0001)表面外延大面积、高质量石墨烯的SiO2插层及原位器件的制备 (a)—(d) SiO2插层过程及原位器件构筑示意图[108]; (e)—(g) 不同制备阶段样品的LEED表征[108]; (h) 石墨烯Hall器件的Raman mapping[108]\r\nFig. 14. Synthesis of insulating SiO2 between graphene and a Ru(0001) substrate enabling electronic-device fabrication: (a)–(d) Schematic of the SiO2 intercalation and finally device fabrication processes[108]; (e)–(g) LEED patterns and corresponding structure models for sample in preparation stages (a)–(c), respectively[108]; (h) graphene G-peak intensity mapping, showing the skeleton of the graphene Hall-bar device in Fig. (d)[108].
    图 14  Ru(0001)表面外延大面积、高质量石墨烯的SiO2插层及原位器件的制备 (a)—(d) SiO2插层过程及原位器件构筑示意图[108]; (e)—(g) 不同制备阶段样品的LEED表征[108]; (h) 石墨烯Hall器件的Raman mapping[108]
    Fig. 14.  Synthesis of insulating SiO2 between graphene and a Ru(0001) substrate enabling electronic-device fabrication: (a)–(d) Schematic of the SiO2 intercalation and finally device fabrication processes[108]; (e)–(g) LEED patterns and corresponding structure models for sample in preparation stages (a)–(c), respectively[108]; (h) graphene G-peak intensity mapping, showing the skeleton of the graphene Hall-bar device in Fig. (d)[108].
    下载: 全尺寸图片 幻灯片

    Guo等[108]进一步对二氧化硅插层后的样品进行结构与物性的表征. 如图15所示, 截面扫描透射电子显微镜(STEM)的结果显示, 薄层二氧化硅插层之后, 石墨烯与Ru基底间的距离为1.1 nm, 界面处的SiO2具有晶态双层结构. STM的结果显示二氧化硅层表面的石墨烯具有完整的六角蜂窝状晶格, 并结合Raman光谱表明SiO2插层之后, 石墨烯依然保持着原有的高质量特性. 随着硅和氧原子插层量的增加, 界面处SiO2由晶态转变为非晶态, 其厚度可达1.8 nm, 如图16所示. 垂直方向的电输运测试表明, 界面处1.8 nm的厚层非晶态SiO2层极大地限制了电子从石墨烯向Ru衬底的输运过程, 成功地实现了石墨烯与Ru衬底间的电学近绝缘. 最后, 基于此样品制备了石墨烯的原位电子学器件, 通过低温/强磁场下的输运测试, 观测到了外延石墨烯的SdH振荡、整数量子霍尔效应以及弱反局域化等现象. 这些现象均来源于石墨烯中二维电子气的本征性质, 进一步证明了绝缘二氧化硅的插层并没有破坏外延石墨烯的大面积、高质量特性, 而且有效地隔绝了石墨烯与金属基底间的耦合作用. 该工作提供了一种与硅基技术融合的、制备高质量、大面积石墨烯单晶的新思路, 为石墨烯材料及其器件的应用奠定了坚实的基础.

    图 15 (a) 薄层晶态二氧化硅插层样品的大面积截面STEM图像[108]; (b) 高分辨STEM图像显示晶态二氧化硅的双层结构[108]; (c) 界面处的EELS谱[108]; (d) 晶态二氧化硅表面石墨烯的STM图像[108]; (e) 晶态二氧化硅插层之后石墨烯的Raman光谱[108]\r\nFig. 15. (a) Large-scale aberration-corrected bright-field STEM image of the bilayer-silica intercalated sample[108]; (b) high resolution STEM image taken at the red box in Fig. (a) clearly shows the atomic structure of the interfacial silica[108]; (c) EELS of Si-L2, 3 edge taken at the intercalation layer[108]; (d) atomic-resolution STM image of the graphene overlayer[108]; (e) Raman spectra of the graphene after intercalation of the crystalline SiO2[108].
    图 15  (a) 薄层晶态二氧化硅插层样品的大面积截面STEM图像[108]; (b) 高分辨STEM图像显示晶态二氧化硅的双层结构[108]; (c) 界面处的EELS谱[108]; (d) 晶态二氧化硅表面石墨烯的STM图像[108]; (e) 晶态二氧化硅插层之后石墨烯的Raman光谱[108]
    Fig. 15.  (a) Large-scale aberration-corrected bright-field STEM image of the bilayer-silica intercalated sample[108]; (b) high resolution STEM image taken at the red box in Fig. (a) clearly shows the atomic structure of the interfacial silica[108]; (c) EELS of Si-L2, 3 edge taken at the intercalation layer[108]; (d) atomic-resolution STM image of the graphene overlayer[108]; (e) Raman spectra of the graphene after intercalation of the crystalline SiO2[108].
    下载: 全尺寸图片 幻灯片
    图 16 (a) 厚层二氧化硅插层样品的界面STEM图像, 显示界面处厚层二氧化硅的厚度达到1.8 nm, 具有非晶态结构[108]; (b) X射线光电子能谱[108]; (c) 低偏压(< 10 mV)下, 对不同厚度二氧化硅插层的样品在垂直方向输运性质测试[108]; (d) 不同温度下的SdH振荡[108]; (e) 2 K下磁阻Rxx以及霍尔电阻Rxy随磁场的变化[108]; (f) 不同温度下纵向电导率在低场范围的变化规律, 与石墨烯的弱反局域理论很好的拟合[108]\r\nFig. 16. (a) STEM image showing an amorphous SiO2 film with thickness of 1.8 nm between graphene and Ru substrate[108]; (b) XPS of the Si 2p and O 1s core levels; (c) vertical transport measurements at small bias (< 10 mV) for Gr/Ru, Gr/1.1 nm-silica/Ru and Gr/1.8 nm-silica/Ru samples[108]; (d) SdH oscillations at different temperatures[108]; (e) magnetoresistance Rxx and Hall resistance Rxy measured at 2 K[108]; (f) corrections of low field conductivity (△σxx) at different temperatures, showing good agreement with the weak antilocalization theory of graphene[108].
    图 16  (a) 厚层二氧化硅插层样品的界面STEM图像, 显示界面处厚层二氧化硅的厚度达到1.8 nm, 具有非晶态结构[108]; (b) X射线光电子能谱[108]; (c) 低偏压(< 10 mV)下, 对不同厚度二氧化硅插层的样品在垂直方向输运性质测试[108]; (d) 不同温度下的SdH振荡[108]; (e) 2 K下磁阻Rxx以及霍尔电阻Rxy随磁场的变化[108]; (f) 不同温度下纵向电导率在低场范围的变化规律, 与石墨烯的弱反局域理论很好的拟合[108]
    Fig. 16.  (a) STEM image showing an amorphous SiO2 film with thickness of 1.8 nm between graphene and Ru substrate[108]; (b) XPS of the Si 2p and O 1s core levels; (c) vertical transport measurements at small bias (< 10 mV) for Gr/Ru, Gr/1.1 nm-silica/Ru and Gr/1.8 nm-silica/Ru samples[108]; (d) SdH oscillations at different temperatures[108]; (e) magnetoresistance Rxx and Hall resistance Rxy measured at 2 K[108]; (f) corrections of low field conductivity (△σxx) at different temperatures, showing good agreement with the weak antilocalization theory of graphene[108].
    下载: 全尺寸图片 幻灯片

    此外, 在另外一些体系中也实现了石墨烯与双元二维材料异质结构的构筑. Dahal和Batzill[139]在石墨烯/Pt(111)外延体系中实现了二维FeO的插层, 构筑了石墨烯/FeO异质结构. 2016年, Al Balushi等[118]利用两步法成功地构筑了石墨烯/GaN二维原子晶体材料异质结构. Picone等[140]报道了石墨烯/Ni(111)界面的二维CrC2材料的构筑, Wang等[141]报道了石墨烯/Ir(111)界面氧化锗的构筑, 等等. 总体而言, 利用插层技术构筑新型二维原子晶体材料异质结构是一个全新的研究领域, 有望在未来基础研究与应用方面取得突破性进展.

    除了前文提到的分子束外延以及石墨烯插层两类方案之外, 另一种可以在真空中构筑新型二维材料纳米结构的方式是利用扫描探针等进行人为的原位操纵. Chen等[142]利用STM针尖实现了对石墨烯纳米结构的原子级精准可控折叠, 构筑出由二维旋转堆垛双层石墨烯纳米结构与一维的类碳纳米管结构组成的新型复合石墨烯纳米结构, 如图17所示. 他们通过扫描探针操控技术实现了石墨烯纳米结构任意方向的原子级精准可控折叠, 并进一步实现了准一维手性碳纳米管异质结构的构筑. 他们应用扫描隧道谱与第一性原理计算确定折叠石墨烯的纳米结构的精确原子构型与局域电子态结构, 发现通过石墨烯“纳米折纸术”得到的准一维纳米管异质结具有不同的能带排列方式.

    图 17 石墨烯“折纸术”的示意图以及STM图像[142]. 利用扫描探针显微镜针尖, 可以对石墨烯纳米岛进行折叠[142]. 利用纳米岛中的一维晶界, 可以构筑具有手性异质结构的一维碳纳米管结构[142]\r\nFig. 17. Schematic and STM images of the graphene origami[142]. The graphene nanoislands can be folded by STM tip[142]. By taking advantage of the natural 1D domain boundaries in the nanoislands, heterostructure of 1D carbon nanotubes with different chirality can be constructed[142].
    图 17  石墨烯“折纸术”的示意图以及STM图像[142]. 利用扫描探针显微镜针尖, 可以对石墨烯纳米岛进行折叠[142]. 利用纳米岛中的一维晶界, 可以构筑具有手性异质结构的一维碳纳米管结构[142]
    Fig. 17.  Schematic and STM images of the graphene origami[142]. The graphene nanoislands can be folded by STM tip[142]. By taking advantage of the natural 1D domain boundaries in the nanoislands, heterostructure of 1D carbon nanotubes with different chirality can be constructed[142].
    下载: 全尺寸图片 幻灯片

    这种方式的优点在于目的性与可控性非常强. 基于这种原子级精准的“折纸术”, 有望实现其他新型二维原子晶体材料的复合叠层结构, 制备出功能纳米结构及其量子器件, 对构筑新型量子材料和量子器件具有重要意义.

    本文重点回顾了基于超高真空环境构筑二维材料的三种方式, 包括分子束外延、石墨烯插层以及扫描探针原位操纵. 三种方式各有优势, 同时也各自存在一定的局限性(图18). 分子束外延相对具有最高的普适性, 然而同时对基底的选择有较高要求, 尤其是对于硅烯、锗烯这类体相非层状的二维材料. 衬底的选择很大程度地决定了外延得到的二维材料的质量与性能. 石墨烯插层是一种新方法, 也具有一定的普适性, 其优势在于构筑出的界面处的二维材料受到表层石墨烯的保护. 这种方法受限于能够进行插层的材料, 另外制备双元和多元二维材料的难度非常高. 利用扫描探针操纵二维材料的方法其优势在于, 原子级精度可控以及可以按照科研人员的意愿来改变和修饰材料. 其不足之处在于不可扩展性. 因此, 研究人员需要根据自己的需求以及材料本身的特性选择合适的制备方案.

    图 18 三种二维材料构筑方式的比较.\r\nFig. 18. Comparison among the three construction methods of 2D materials.
    图 18  三种二维材料构筑方式的比较.
    Fig. 18.  Comparison among the three construction methods of 2D materials.
    下载: 全尺寸图片 幻灯片

    当然, 材料的制备方法也是一直发展的. 希望通过材料学家们的共同努力, 可以开发出更多更好的二维材料制备方法, 也希望这些方法可以更大地拓展材料库, 早日实现二维材料在人类生产生活中的应用.

    References

    [1]

    Novoselov K S, Geim A K, Morozov S V, Jiang D, Zhang Y, Dubonos S V, Grigorieva I V, Firsov A A 2004 Science 306 666Google Scholar

    [2]

    Castro Neto A H, Guinea F, Peres N M R, Novoselov K S, Geim A K 2009 Rev. Mod. Phys. 81 109Google Scholar

    [3]

    Zhang X D, Xie Y 2013 Chem. Soc. Rev. 42 8187Google Scholar

    [4]

    Novoselov K S, Mishchenko A, Carvalho A, Neto A H C 2016 Science 353 aac9439Google Scholar

    [5]

    Li G, Zhang Y Y, Guo H, Huang L, Lu H L, Lin X, Wang Y L, Du S X, Gao H J 2018 Chem. Soc. Rev. 47 6073Google Scholar

    [6]

    Takeda K, Shiraishi K 1994 Phys. Rev. B 50 14916Google Scholar

    [7]

    Guzman-Verri G G, Voon L C L Y 2007 Phys. Rev. B 76 075131Google Scholar

    [8]

    Liu C C, Jiang H, Yao Y G 2011 Phys. Rev. B 84 195430Google Scholar

    [9]

    Liu C C, Feng W X, Yao Y G 2011 Phys. Rev. Lett. 107 076802Google Scholar

    [10]

    Lalmi B, Oughaddou H, Enriquez H, Kara A, Vizzini S, Ealet B, Aufray B 2010 Appl. Phys. Lett. 97 223109Google Scholar

    [11]

    Vogt P, De Padova P, Quaresima C, Avila J, Frantzeskakis E, Asensio M C, Resta A, Ealet B, Le Lay G 2012 Phys. Rev. Lett. 108 155501Google Scholar

    [12]

    Feng B, Ding Z, Meng S, Yao Y, He X, Cheng P, Chen L, Wu K 2012 Nano Lett. 12 3507Google Scholar

    [13]

    Lin C L, Arafune R, Kawahara K, Tsukahara N, Minamitani E, Kim Y, Takagi N, Kawai M 2012 Appl. Phys. Express 5 045802Google Scholar

    [14]

    Onoda J, Yabuoshi K, Miyazaki H, Sugimoto Y 2017 Phys. Rev. B 96 241302Google Scholar

    [15]

    Lin C L, Arafune R, Kawahara K, Kanno M, Tsukahara N, Minamitani E, Kim Y, Kawai M, Takagi N 2013 Phys. Rev. Lett. 110 076801Google Scholar

    [16]

    Feng Y, Liu D F, Feng B J, Liu X, Zhao L, Xie Z J, Liu Y, Liang A J, Hu C, Hu Y, He S L, Liu G D, Zhang J, Chen C T, Xu Z Y, Chen L, Wu K H, Liu Y T, Lin H, Huang Z Q, Hsu C H, Chuang F C, Bansil A, Zhou X J 2016 Proc. Natl. Acad. Sci. U. S. A. 113 14656Google Scholar

    [17]

    Fleurence A, Friedlein R, Ozaki T, Kawai H, Wang Y, Yamada-Takamura Y 2012 Phys. Rev. Lett. 108 245501Google Scholar

    [18]

    Meng L, Wang Y L, Zhang L Z, Du S X, Wu R T, Li L F, Zhang Y, Li G, Zhou H T, Hofer W A, Gao H J 2013 Nano Lett. 13 685Google Scholar

    [19]

    Huang L, Zhang Y F, Zhang Y Y, Xu W Y, Que Y D, Li E, Pan J B, Wang Y L, Liu Y Q, Du S X, Pantelides S T, Gao H J 2017 Nano Lett. 17 1161Google Scholar

    [20]

    Brumfiel G 2013 Nature 495 152Google Scholar

    [21]

    De Padova P, Ottaviani C, Quaresima C, Olivieri B, Imperatori P, Salomon E, Angot T, Quagliano L, Romano C, Vona A, Muniz-Miranda M, Generosi A, Paci B, Le Lay G 2014 2 D Mater. 1 021003
    [22]

    Du Y, Zhuang J C, Wang J O, Li Z, Liu H, Zhao J, Xu X, Feng H, Chen L, Wu K, Wang X, Dou S X 2016 Sci. Adv. 2 e1600067Google Scholar

    [23]

    Tao L, Cinquanta E, Chiappe D, Grazianetti C, Fanciulli M, Dubey M, Molle A, Akinwande D 2015 Nat. Nanotechnol. 10 227Google Scholar

    [24]

    Li L F, Lu S Z, Pan J B, Qin Z H, Wang Y Q, Wang Y L, Cao G Y, Du S X, Gao H J 2014 Adv. Mater. 26 4820Google Scholar

    [25]

    Qin Z H, Pan J B, Lu S Z, Yan S, Wang Y L, Du S X, Gao H J, Cao G Y 2017 Adv. Mater. 29 1606046Google Scholar

    [26]

    Acun A, Zhang L, Bampoulis P, Farmanbar M, van Houselt A, Rudenko A N, Lingenfelder M, Brocks G, Poelsema B, Katsnelson M I, Zandvliet H J W 2015 J. Phys. Condens. Matter 27 442001
    [27]

    Davila M E, Xian L, Cahangirov S, Rubio A, Le Lay G 2014 New J. Phys. 16 095002Google Scholar

    [28]

    Derivaz M, Dentel D, Stephan R, Hanf M C, Mehdaoui A, Sonnet P, Pirri C 2015 Nano Lett. 15 2510Google Scholar

    [29]

    Zhang L, Bampoulis P, Rudenko A N, Yao Q, van Houselt A, Poelsema B, Katsnelson M I, Zandvliet H J W 2016 Phys. Rev. Lett. 116 256804Google Scholar

    [30]

    Lin C H, Huang A, Pai W W, Chen W C, Chen T Y, Chang T R, Yukawa R, Cheng C M, Mou C Y, Matsuda I, Chiang T C, Jeng H T, Tang S J 2018 Phys. Rev. Mater. 2 024003Google Scholar

    [31]

    Chou B H, Huang Z Q, Hsu C H, Chuang F C, Liu Y T, Lin H, Bansil A 2014 New J. Phys. 16 115008Google Scholar

    [32]

    Zhu F F, Chen W J, Xu Y, Gao C L, Guan D D, Liu C H, Qian D, Zhang S C, Jia J F 2015 Nat. Mater. 14 1020Google Scholar

    [33]

    Xu C Z, Chan Y H, Chen P, Wang X X, Flototto D, Hlevyack J A, Bian G, Mo S K, Chou M Y, Chiang T C 2018 Phys. Rev. B 97 035122Google Scholar

    [34]

    Zang Y Y, Jiang T, Gong Y, Guan Z Y, Liu C, Liao M H, Zhu K J, Li Z, Wang L L, Li W, Song C L, Zhang D, Xu Y, He K, Ma X C, Zhang S C, Xue Q K 2018 Adv. Funct. Mater. 28 1802723Google Scholar

    [35]

    Xu C Z, Chan Y H, Chen Y G, Chen P, Wang X X, Dejoie C, Wong M H, Hlevyack J A, Ryu H J, Kee H Y, Tamura N, Chou M Y, Hussain Z, Mo S K, Chiang T C 2017 Phys. Rev. Lett. 118 146402Google Scholar

    [36]

    Zheng X H, Zhang J F, Tong B, Du R R 2020 2 D Mater. 7 011001
    [37]

    Deng J L, Xia B Y, Ma X C, Chen H Q, Shan H, Zhai X F, Li B, Zhao A D, Xu Y, Duan W H, Zhang S C, Wang B, Hou J G 2018 Nat. Mater. 17 1081Google Scholar

    [38]

    Yuhara J, Fujii Y, Nishino K, Isobe N, Nakatake M, Xian L D, Rubio A, Le Lay G 2018 2 D Mater. 5 025002
    [39]

    Yuhara J, Le Lay G 2020 Jpn. J. Appl. Phys. 59 SN0801Google Scholar

    [40]

    Dong X, Zhang L Z, Yoon M N, Zhang P P 2021 2 D Mater. 8 045003
    [41]

    Yu X L, Huang L, Wu J S 2017 Phys. Rev. B 95 125113Google Scholar

    [42]

    Huang Z Q, Hsu C H, Chuang F C, Liu Y T, Lin H, Su W S, Ozolins V, Bansil A 2014 New J. Phys. 16 105018Google Scholar

    [43]

    Yu X L, Wu J S 2018 Phys. Chem. Chem. Phys. 20 2296Google Scholar

    [44]

    Rivero P, Yan J A, Garcia-Suarez V M, Ferrer J, Barraza-Lopez S 2014 Phys. Rev. B 90 241408(R)
    [45]

    Kim J, Qin S Y, Yao W, Niu Q, Chou M Y, Shih C K 2010 Proc. Natl. Acad. Sci. U. A. S. 107 12761Google Scholar

    [46]

    Zhang T, Cheng P, Li W J, Sun Y J, Wang G, Zhu X G, He K, Wang L L, Ma X C, Chen X, Wang Y Y, Liu Y, Lin H Q, Jia J F, Xue Q K 2010 Nat. Phys. 6 104Google Scholar

    [47]

    Brun C, Cren T, Cherkez V, Debontridder F, Pons S, Fokin D, Tringides M C, Bozhko S, Ioffe L B, Altshuler B L, Roditchev D 2014 Nat. Phys. 10 444Google Scholar

    [48]

    Roditchev D, Brun C, Serrier-Garcia L, Cuevas J C, Bessa V H L, Milosevic M V, Debontridder F, Stolyarov V, Cren T 2015 Nat. Phys. 11 332Google Scholar

    [49]

    Yuhara J, He B J, Matsunami N, Nakatake M, Le Lay G 2019 Adv. Mater. 31 1901017Google Scholar

    [50]

    Bihlmayer G, Sassmannshausen J, Kubetzka A, Blugel S, von Bergmann K, Wiesendanger R 2020 Phys. Rev. Lett. 124 126401Google Scholar

    [51]

    Liu H S, Gao J F, Zhao J J 2013 Sci. Rep. 3 3238Google Scholar

    [52]

    Liu Y Y, Penev E S, Yakobson B I 2013 Angew. Chem. Int. Ed. 52 3156Google Scholar

    [53]

    Mannix A J, Zhou X F, Kiraly B, Wood J D, Alducin D, Myers B D, Liu X L, Fisher B L, Santiago U, Guest J R, Yacaman M J, Ponce A, Oganov A R, Hersam M C, Guisinger N P 2015 Science 350 1513Google Scholar

    [54]

    Feng B J, Zhang J, Zhong Q, Li W B, Li S, Li H, Cheng P, Meng S, Chen L, Wu K H 2016 Nat. Chem. 8 564
    [55]

    Chen C Y, Lü H F, Zhang P, Zhuo Z W, Wang Y, Ma C, Li W B, Wang X G, Feng B J, Cheng P, Wu X J, Wu K H, Chen L 2021 Nat. Chem. 14 25
    [56]

    Liu X L, Li Q C, Ruan Q Y, Rahn M S, Yakobson B I, Hersam M C 2021 Nat. Mater. 21 35
    [57]

    Xia F N, Wang H, Jia Y C 2014 Nat. Commun. 5 4458Google Scholar

    [58]

    Carvalho A, Wang M, Zhu X, Rodin A S, Su H B, Neto A H C 2016 Nat. Rev. Mater. 1 16061Google Scholar

    [59]

    Akhtar M, Anderson G, Zhao R, Alruqi A, Mroczkowska J E, Sumanasekera G, Jasinski J B 2017 NPJ 2D Mater. Appl. 1 5Google Scholar

    [60]

    Zhang J L, Zhao S T, Han C, Wang Z Z, Zhong S, Sun S, Guo R, Zhou X, Gu C D, Di Yuan K, Li Z Y, Chen W 2016 Nano Lett. 16 4903Google Scholar

    [61]

    Zhu Z, Tomanek D 2014 Phys. Rev. Lett. 112 176802Google Scholar

    [62]

    Wu X, Shao Y, Liu H, Feng Z, Wang Y L, Sun J T, Liu C, Wang J O, Liu Z L, Zhu S Y, Wang Y Q, Du S X, Shi Y G, Ibrahim K, Gao H J 2017 Adv. Mater. 29 1605407Google Scholar

    [63]

    Zhu S Y, Shao Y, Wang E, Cao L, Li X Y, Liu Z L, Liu C, Liu L W, Wang J O, Ibrahim K, Sun J T, Wang Y L, Du S X, Gao H J 2019 Nano Lett. 19 6323Google Scholar

    [64]

    Shao Y, Liu Z L, Cheng C, Wu X, Liu H, Liu C, Wang J O, Zhu S Y, Wang Y Q, Shi D X, Ibrahim K, Sun J T, Wang Y L, Gao H J 2018 Nano Lett. 18 2133Google Scholar

    [65]

    Reis F, Li G, Dudy L, Bauernfeind M, Glass S, Hanke W, Thomale R, Schafer J, Claessen R 2017 Science 357 287Google Scholar

    [66]

    Li L F, Wang Y L, Xie S Y, Li X B, Wang Y Q, Wu R T, Sun H B, Zhang S B, Gao H J 2013 Nano Lett. 13 4671Google Scholar

    [67]

    Gao H J, Gao L 2010 Prog. Surf. Sci. 85 28Google Scholar

    [68]

    Gao H J, Xue Z Q, Wang K Z, Wu Q D, Pang S 1996 Appl. Phys. Lett. 68 2192Google Scholar

    [69]

    Gao H J, Sohlberg K, Xue Z Q, Chen H Y, Hou S M, Ma L P, Fang X W, Pang S J, Pennycook S J 2000 Phys. Rev. Lett. 84 1780Google Scholar

    [70]

    Feng M, Guo X F, Lin X, He X B, Ji W, Du S X, Zhang D Q, Zhu D B, Gao H J 2005 J. Am. Chem. Soc. 127 15338Google Scholar

    [71]

    Feng M, Gao L, Deng Z T, Ji W, Guo X F, Du S X, Shi D X, Zhang D Q, Zhu D B, Gao H J 2007 J. Am. Chem. Soc. 129 2204Google Scholar

    [72]

    Du S X, Gao H J, Seidel C, Tsetseris L, Ji W, Kopf H, Chi L F, Fuchs H, Pennycook S J, Pantelides S T 2006 Phys. Rev. Lett. 97 156105Google Scholar

    [73]

    Shi D, Ji W, Lin X, He X, Lian J, Gao L, Cai J, Lin H, Du S, Lin F, Seidel C, Chi L, Hofer W, Fuchs H, Gao H J 2006 Phys. Rev. Lett. 96 226101Google Scholar

    [74]

    Zhang S, Song Y, Li H, Li J M, Qian K, Liu C, Wang J O, Qian T, Zhang Y Y, Lu J C, Ding H, Lin X, Pan J B, Du S X, Gao H J 2020 Chin. Phys. Lett. 37 068103Google Scholar

    [75]

    Zheng C, Zhao D P, Cai X Q, Huang W T, Meng F Q, Zhang Q H, Tang L, Hu X P, Gu L, Ji S H, Chen X 2020 Chin. Phys. Lett. 37 087401Google Scholar

    [76]

    王兴悦, 张辉, 阮子林, 郝振亮, 杨孝天, 蔡金明, 卢建臣 2020 物理学报 69 118101Google Scholar

    Wang X Y, Zhang H, Ruan Z L, Hao Z L, Yang X T, Cai J M, Lu J C 2020 Acta Phys. Sin. 69 118101Google Scholar

    [77]

    Lu J C, Bao D L, Qian K, Zhang S, Chen H, Lin X, Du S X, Gao H J 2017 ACS Nano 11 1689Google Scholar

    [78]

    Lu J C, Niu G F, Ren X, Bao D L, Chen H, Yang H T, Lin X, Du S X, Gao H J 2021 Nanoscale 13 19165Google Scholar

    [79]

    Kezilebieke S, Huda N, Vano V, Aapro M, Ganguli S C, Silveira O J, Glodzik S, Foster A S, Ojanen T, Liljeroth P 2020 Nature 588 424Google Scholar

    [80]

    Li E, Zhang R Z, Li H, Liu C, Li G, Wang J O, Qian T, Ding H, Zhang Y Y, Du S X, Lin X, Gao H J 2018 Chin. Phys. B 27 086804Google Scholar

    [81]

    Ugeda M M, Bradley A J, Shi S F, da Jornada F H, Zhang Y, Qiu D Y, Ruan W, Mo S K, Hussain Z, Shen Z X, Wang F, Louie S G, Crommie M F 2014 Nat. Mater. 13 1091Google Scholar

    [82]

    Li E, Wang D F, Fan P, Zhang R Z, Zhang Y Y, Li G, Mao J H, Wang Y L, Lin X, Du S X, Gao H J 2018 Nano Res. 11 5858Google Scholar

    [83]

    Fan P, Zhang R Z, Qi J, Li E, Qian G J, Chen H, Wang D F, Zheng Q, Wang Q, Lin X, Zhang Y Y, Du S X, Hofer W A, Gao H J 2020 Chin. Phys. B 29 098102Google Scholar

    [84]

    Fan P, Qian G J, Wang D F, Li E, Wang Q, Chen H, Lin X, Gao H J 2021 Chin. Phys. B 30 018105Google Scholar

    [85]

    Wang Y L, Li L F, Yao W, Song S R, Sun J T, Pan J B, Ren X, Li C, Okunishi E, Wang Y Q, Wang E Y, Shao Y, Zhang Y Y, Yang H T, Schwier E F, Iwasawa H, Shimada K, Taniguchi M, Cheng Z H, Zhou S Y, Du S X, Pennycook S J, Pantelides S T, Gao H J 2015 Nano Lett. 15 4013Google Scholar

    [86]

    Wang Y Q, Wu X, Wang Y L, Shao Y, Lei T, Wang J O, Zhu S Y, Guo H M, Zhao L X, Chen G F, Nie S M, Weng H M, Ibrahim K, Dai X, Fang Z, Gao H J 2016 Adv. Mater. 28 5013Google Scholar

    [87]

    Lin X, Lu J C, Shao Y, Zhang Y Y, Wu X, Pan J B, Gao L, Zhu S Y, Qian K, Zhang Y F, Bao D L, Li L F, Wang Y Q, Liu Z L, Sun J T, Lei T, Liu C, Wang J O, Ibrahim K, Leonard D N, Zhou W, Guo H M, Wang Y L, Du S X, Pantelides S T, Gao H J 2017 Nat. Mater. 16 717Google Scholar

    [88]

    Gao L, Sun J T, Lu J C, Li H, Qian K, Zhang S, Zhang Y Y, Qian T, Ding H, Lin X, Du S, Gao H J 2018 Adv. Mater. 30 1707055Google Scholar

    [89]

    Dong L, Wang A W, Li E, Wang Q, Li G, Huan Q, Gao H J 2019 Chin. Phys. Lett. 36 028102Google Scholar

    [90]

    Wang A W, Liu Z Y, Pan J B, Li Q C, Li G, Huan Q, Du S X, Gao H J 2020 Chin. Phys. B 29 078102Google Scholar

    [91]

    Qian K, Gao L, Chen X Y, Li H, Zhang S, Zhang X L, Zhu S Y, Yan J H, Bao D L, Cao L, Shi J A, Lu J C, Liu C, Wang J, Qian T, Ding H, Gu L, Zhou W, Zhang Y Y, Lin X, Du S X, Ouyang M, Pantelides S T, Gao H J 2020 Adv. Mater. 32 1908314Google Scholar

    [92]

    Li S H, Gu G X, Liu E K, Cheng P, Feng B J, Li Y Q, Chen L, Wu K H 2020 ACS Appl. Electron. Mater. 2 126Google Scholar

    [93]

    Gong Y, Guo J W, Li J H, Zhu K J, Liao M H, Liu X Z, Zhang Q H, Gu L, Tang L, Feng X, Zhang D, Li W, Song C L, Wang L L, Yu P, Chen X, Wang Y Y, Yao H, Duan W H, Xu Y, Zhang S C, Ma X C, Xue Q K, He K 2019 Chin. Phys. Lett. 36 076801Google Scholar

    [94]

    Wang Q Y, Li Z, Zhang W H, Zhang Z C, Zhang J S, Li W, Ding H, Ou Y B, Deng P, Chang K, Wen J, Song C L, He K, Jia J F, Ji S H, Wang Y Y, Wang L L, Chen X, Ma X C, Xue Q K 2012 Chin. Phys. Lett. 29 037402Google Scholar

    [95]

    Chang K, Deng P, Zhang T, Lin H C, Zhao K, Ji S H, Wang L L, He K, Ma X C, Chen X, Xue Q K 2015 EPL 109 28003Google Scholar

    [96]

    Sakoda M, Iida K, Naito M 2018 Supercond. Sci. Technol. 31 093001Google Scholar

    [97]

    Li Z, Sang L N, Liu P, Yue Z J, Fuhrer M S, Xue Q K, Wang X L 2021 Small 17 1904788Google Scholar

    [98]

    Zhang Y, He K, Chang C Z, Song C L, Wang L L, Chen X, Jia J F, Fang Z, Dai X, Shan W Y, Shen S Q, Niu Q, Qi X L, Zhang S C, Ma X C, Xue Q K 2010 Nat. Phys. 6 584Google Scholar

    [99]

    Sun H H, Zhang K W, Hu L H, Li C, Wang G Y, Ma H Y, Xu Z A, Gao C L, Guan D D, Li Y Y, Liu C H, Qian D, Zhou Y, Fu L, Li S C, Zhang F C, Jia J F 2016 Phys. Rev. Lett. 116 257003Google Scholar

    [100]

    Loffler D, Uhlrich J J, Baron M, Yang B, Yu X, Lichtenstein L, Heinke L, Buchner C, Heyde M, Shaikhutdinov S, Freund H J, Wlodarczyk R, Sierka M, Sauer J 2010 Phys. Rev. Lett. 105 146104Google Scholar

    [101]

    Liang Y, Chen Y J, Sun Y W, Xu S P, Wu J X, Tan C W, Xu X F, Yuan H T, Yang L X, Chen Y L, Gao P, Guo J D, Peng H L 2019 Adv. Mater. 31 1901964Google Scholar

    [102]

    Mao J H, Huang L, Pan Y, Gao M, He J F, Zhou H T, Guo H M, Tian Y, Zou Q, Zhang L Z, Zhang H G, Wang Y L, Du S X, Zhou X J, Castro Neto A H, Gao H J 2012 Appl. Phys. Lett. 100 093101Google Scholar

    [103]

    Li L F, Wang Y L, Meng L, Wu R T, Gao H J 2013 Appl. Phys. Lett. 102 093106Google Scholar

    [104]

    Huang L, Pan Y, Pan L D, Gao M, Xu W Y, Que Y D, Zhou H T, Wang Y L, Du S X, Gao H J 2011 Appl. Phys. Lett. 99 163107Google Scholar

    [105]

    Li G, Zhou H T, Pan L D, Zhang Y, Huang L, Xu W Y, Du S X, Ouyang M, Ferrari A C, Gao H J 2015 J. Am. Chem. Soc. 137 7099Google Scholar

    [106]

    Que Y D, Zhang Y, Wang Y L, Huang L, Xu W Y, Tao J, Wu L J, Zhu Y M, Kim K, Weinl M, Schreck M, Shen C M, Du S X, Liu Y Q, Gao H J 2015 Adv. Mater. Interfaces 2 1400543Google Scholar

    [107]

    Li G, Zhang L Z, Xu W Y, Pan J B, Song S R, Zhang Y, Zhou H T, Wang Y L, Bao L H, Zhang Y Y, Du S X, Ouyang M, Pantelides S T, Gao H J 2018 Adv. Mater. 30 1804650Google Scholar

    [108]

    Guo H, Wang X Y, Huang L, Jin X, Yang Z Z, Zhou Z, Hu H, Zhang Y Y, Lu H L, Zhang Q H, Shen C M, Lin X, Gu L, Dai Q, Bao L H, Du S X, Hofer W, Pantelides S T, Gao H J 2020 Nano Lett. 20 8584Google Scholar

    [109]

    Enderlein C, Kim Y S, Bostwick A, Rotenberg E, Horn K 2010 New J. Phys. 12 033014Google Scholar

    [110]

    Riedl C, Coletti C, Iwasaki T, Zakharov A A, Starke U 2009 Phys. Rev. Lett. 103 246804Google Scholar

    [111]

    Jin L, Fu Q, Mu R T, Tan D L, Bao X H 2011 Phys. Chem. Chem. Phys. 13 16655Google Scholar

    [112]

    Feng X F, Maier S, Salmeron M 2012 J. Am. Chem. Soc. 134 5662Google Scholar

    [113]

    Lu J, Neto A H C, Loh K P 2012 Nat. Commun. 3 823Google Scholar

    [114]

    Mu R T, Fu Q, Jin L, Yu L, Fang G Z, Tan D L, Bao X H 2012 Angew. Chem. Int. Ed. 51 4856Google Scholar

    [115]

    Sicot M, Leicht P, Zusan A, Bouvron S, Zander O, Weser M, Dedkov Y S, Horn K, Fonin M 2012 ACS Nano 6 151Google Scholar

    [116]

    Decker R, Brede J, Atodiresei N, Caciuc V, Blugel S, Wiesendanger R 2013 Phys. Rev. B 87 041403
    [117]

    Petrovic M, Rakic I S, Runte S, Busse C, Sadowski J T, Lazic P, Pletikosic I, Pan Z H, Milun M, Pervan P, Atodiresei N, Brako R, Sokcevic D, Valla T, Michely T, Kralj M 2013 Nat. Commun. 4 2772Google Scholar

    [118]

    Al Balushi Z Y, Wang K, Ghosh R K, Vila R A, Eichfeld S M, Caldwell J D, Qin X Y, Lin Y C, DeSario P A, Stone G, Subramanian S, Paul D F, Wallace R M, Datta S, Redwing J M, Robinson J A 2016 Nat. Mater. 15 1166Google Scholar

    [119]

    Sutter P, Sadowski J T, Sutter E A 2010 J. Am. Chem. Soc. 132 8175Google Scholar

    [120]

    Xia C, Watcharinyanon S, Zakharov A A, Yakimova R, Hultman L, Johansson L I, Virojanadara C 2012 Phys. Rev. B 85 045418Google Scholar

    [121]

    Pan Y, Shi D X, Gao H J 2007 Chin. Phys. 16 3151Google Scholar

    [122]

    Pan Y, Zhang H G, Shi D X, Sun J T, Du S X, Liu F, Gao H J 2009 Adv. Mater. 21 2777Google Scholar

    [123]

    Cui Y, Gao J F, Jin L, Zhao J J, Tan D L, Fu Q, Bao X H 2012 Nano Res. 5 352Google Scholar

    [124]

    Cao Y, Fatemi V, Fang S, Watanabe K, Taniguchi T, Kaxiras E, Jarillo-Herrero P 2018 Nature 556 43Google Scholar

    [125]

    Cao Y, Fatemi V, Demir A, Fang S, Tomarken S L, Luo J Y, Sanchez-Yamagishi J D, Watanabe K, Taniguchi T, Kaxiras E, Ashoori R C, Jarillo-Herrero P 2018 Nature 556 80Google Scholar

    [126]

    Andrei E Y, MacDonald A H 2020 Nat. Mater. 19 1265Google Scholar

    [127]

    Castro E V, Novoselov K S, Morozov S V, Peres N M R, Dos Santos J M B L, Nilsson J, Guinea F, Geim A K, Castro Neto A H 2007 Phys. Rev. Lett. 99 216802Google Scholar

    [128]

    Zhang Y B, Tang T T, Girit C, Hao Z, Martin M C, Zettl A, Crommie M F, Shen Y R, Wang F 2009 Nature 459 820Google Scholar

    [129]

    Oostinga J B, Heersche H B, Liu X L, Morpurgo A F, Vandersypen L M K 2008 Nat. Mater. 7 151Google Scholar

    [130]

    Mak K F, Lui C H, Shan J, Heinz T F 2009 Phys. Rev. Lett. 102 256405Google Scholar

    [131]

    Choi S M, Jhi S H, Son Y W 2010 Nano Lett. 10 3486Google Scholar

    [132]

    Ohta T, Bostwick A, Seyller T, Horn K, Rotenberg E 2006 Science 313 951Google Scholar

    [133]

    Samuels A J, Carey J D 2013 ACS Nano 7 2790Google Scholar

    [134]

    Zhang W J, Lin C T, Liu K K, Tite T, Su C Y, Chang C H, Lee Y H, Chu C W, Wei K H, Kuo J L, Li L J 2011 ACS Nano 5 7517Google Scholar

    [135]

    Tian X Q, Xu J B, Wang X M 2010 J. Phys. Chem. B 114 11377Google Scholar

    [136]

    Wang Y Y, Ni Z Y, Liu Q H, Quhe R G, Zheng J X, Ye M, Yu D P, Shi J J, Yang J B, Li J, Lu J 2015 Adv. Funct. Mater. 25 68Google Scholar

    [137]

    Guo H, Wang X Y, Lu H L, Bao L H, Peng H, Qian K, Ma J J, Li G, Huang L, Lin X, Zhang Y Y, Du S X, Pantelides S T, Gao H J 2019 2 D Mater. 6 045044
    [138]

    Guo H, Zhang R Z, Li H, Wang X Y, Lu H L, Qian K, Li G, Huang L, Lin X, Zhang Y Y, Ding H, Du S X, Pantelides S T, Gao H J 2020 Nano Lett. 20 2674Google Scholar

    [139]

    Dahal A, Batzill M 2015 Sci. Rep. 5 11378Google Scholar

    [140]

    Picone A, Giannotti D, Finazzi M, Duo L, Ciccacci F, Brambilla A 2017 J. Phys. Chem. C 121 16803Google Scholar

    [141]

    Wang X Y, Guo H, Lu J C, Lu H L, Lin X, Shen C M, Bao L H, Du S X, Gao H J 2021 Chin. Phys. B 30 048102Google Scholar

    [142]

    Chen H, Zhang X L, Zhang Y Y, Wang D F, Bao D L, Que Y D, Xiao W D, Du S X, Ouyang M, Pantelides S T, Gao H J 2019 Science 365 1036Google Scholar

  • 图 1  不同基底表面硅烯的分子束外延生长 硅烯在Ag(111)[11]　(a) ZrB2(0001)[17] (b) Ir(111)[18] (c) 和Ru(0001)[19] (d)表面生长的STM图像

    Figure 1.  Molecular beam epitaxial growth of silicene monolayers on different substrates: STM images of silicene monolayer on Ag(111)[11] (a) ZrB2(0001)[17] (b) Ir(111)[18] (c) and Ru(0001)[19] (d), respectively.

    DownLoad: Full-Size Img PowerPoint

    图 2  (a), (b) 单层锗烯在Pt(111)表面外延生长的STM图像(a)和原子模型示意图(b)[24]; (c), (d) 双层锗烯在Cu(111)表面外延生长的STM图像(c)和原子模型示意图(d)[25]

    Figure 2.  (a), (b) STM image (a) and atomic model (b) of germanene monolayer on Pt(111)[24]; (c), (d) STM image (c) and atomic model (d) of germanene bilayer on Cu(111)[25].

    DownLoad: Full-Size Img PowerPoint

    图 3  锡烯在不同衬底上的分子束外延生长　(a) 单层锡烯在Bi2Te3(111)表面外延生长的STM图像[32]; (b) InSb(111)表面外延生长锡烯和钾掺杂锡烯在Г点附近的能带结构[33]; (c), (d) Cu(111)表面外延生长纯平锡烯的大面积STM图像(c)和原子分辨图像(d)[37]; (e) Ir(111)上外延氮化硼表面生长锡烯的STM图像[40]

    Figure 3.  Molecular beam epitaxial growth of stanene monolayers on different substrates: (a) STM image of buckled stanene on Bi2Te3(111)[32]; (b) band structure of as-grown and K doped stanene on InSb(111)[33]; (c), (d) large-scale (c) and atomically-resolved (d) STM images of flat stanene on Cu(111)[37]; (e) STM image of stanene on BN/Ir(111)[40].

    DownLoad: Full-Size Img PowerPoint

    图 4  铅烯在不同衬底上的分子束外延生长 (a), (b) 单层铅烯在Pd(111)表面外延生长的大面积(a)和原子分辨(b) STM图像[49]; (c), (d) 单层铅烯在Fe/Ir(111)表面外延生长的原子分辨STM图像(c)和原子结构模型(d)[50]; (e) 单层铅烯在Fe/Ir(111)表面外延生长的大面积STM图像[50]

    Figure 4.  Molecular beam epitaxial growth of plumbene monolayers on different substrates: (a), (b) Large-scale (a) and atomically-resolved (b) STM image of planar plumbene on Pd(111)[49];(c), (d) atomically-resolved STM image (c) and atomic model of plumbene on monolayer Fe on Ir(111)[50]; (e) large-scale STM image of planar plumbene on monolayer Fe on Ir(111)[50].

    DownLoad: Full-Size Img PowerPoint

    图 5  单层和双层硼烯的分子束外延生长 (a)—(d) 单层硼烯在Ag(111)表面外延生长的STM图像[53,54]; (e), (f) 双层硼烯在Cu(111)表面外延生长的STM图像[55]; (g), (h) 双层硼烯在Ag(111)表面外延生长的STM图像[56]

    Figure 5.  Molecular beam epitaxial growth of borophene monolayers and bilayers: (a)–(d) STM images of monolayer borophene on Ag(111)[53,54]; (e), (f) STM images of bilayer borophene on Cu(111)[55]; (g), (h) STM images of bilayer borophene on Ag(111)[56].

    DownLoad: Full-Size Img PowerPoint

    图 6  (a), (b) 单层蓝磷在Au(111)表面外延生长的STM图像(a)和原子模型示意图(b)[60]; (c), (d)单层锑烯在PdTe2表面外延生长的STM图像(c)和原子模型示意图(d)[62]; (e) 锑烯单层岛在Cu(111)表面外延生长的STM图像; (f) 跨过锑烯单层岛的扫描隧道谱[63]; (g), (h) 单层铋烯在SiC表面外延生长的STM图像(g)和原子模型示意图(h)[65]

    Figure 6.  (a), (b) STM image (a) and atomic model (b) of monolayer blue phosphorus on Au(111)[60]; (c), (d) STM image (c) and atomic model (d) of monolayer antimonene on PdTe2[62]; (e) STM image of monolayer antimonene on Cu(111); (f) Waterfall-like dI/dV spectra along the arrow in Fig. (e)[63]; (g), (h) STM image (g) and atomic model (h) of monolayer bismuthene on SiC[65].

    DownLoad: Full-Size Img PowerPoint

    图 7  (a) Ir(111)表面大面积单层铪的STM图像; (b) 原子分辨的单层铪STM图像; (c) 铪烯的STM图像、STM模拟图像以及原子结构示意图[66]

    Figure 7.  (a) Large-scale STM image of monolayer Hf on Ir(111); (b) Atomically-resolved STM image of monolayer Hf on Ir(111); (c) The STM image, simulated STM image, and atomic model of a Hafnene monolayer on Ir(111), showing honeycomb Hf lattice[66].

    DownLoad: Full-Size Img PowerPoint

    图 8  (a) Au(111)表面单层MoSe2岛的STM图像; (b) MoSe2岛的原子分辨STM图像; (c), (d) 大面积(c)和原子分辨(d)的Mo边界STM图像; (e) MoSe2上不同区域的dI/dV谱线; (f) MoSe2岛边界上不同位置的dI/dV谱线[77]

    Figure 8.  (a) STM image of monolayer MoSe2 islands on Au(111) substrate; (b) atomic-resolved STM image of single-layer MoSe2 with hexagonal lattice; (c), (d) large-scale (c) and atomically resolved (d) STM image of Mo edge; (e) normalized dI/dV curves obtained on the three different domains of MoSe2 on Au(111); (f) Six normalized dI/dV curves taken on the six edges of one MoSe2 island[77].

    DownLoad: Full-Size Img PowerPoint

    图 9  (a) 双层石墨烯/碳化硅衬底上生长的大面积多层PdTe2[80]; (b) 双层石墨烯/碳化硅衬底上生长的单层MoSe2[81]; (c) 石墨烯化碳化硅衬底上生长的PdSe2; (d) 在跨过单层和双层石墨烯/碳化硅衬底上连续生长的双层PdSe2上测得的扫描隧道谱[82]; (e) 石墨烯化碳化硅衬底上生长的Pd2Se3[83]; (f) 跨过单层和双层Pd2Se3台阶测得的扫描隧道谱[84]

    Figure 9.  (a) Multi-layer PdTe2 on bilayer graphene on SiC substrate[80]; (b) monolayer MoSe2 on bilayer graphene on SiC substrate[81]; (c) bilayer PdSe2 on bilayer graphene on SiC substrate; (d) dI/dV spectra taken on bilayer PdSe2 on top of mono- and bi- layer graphene substrate[82]; (e) Pd2Se3 on bilayer graphene on SiC substrate[83]; (d) dI/dV spectra taken across mono- and bi- layer Pd2Se3[84]

    DownLoad: Full-Size Img PowerPoint

    图 10  (a), (b) 1T/1H相的PtSe2三角图案的结构示意图与STM图像[87]; (c), (d) Cu(111)表面CuSe的周期性三角孔洞结构[87]; (e)—(g) CuSe的扫描透射电镜图像、电镜模拟图像以及原子结构示意图[87]

    Figure 10.  (a), (b) The schematic and STM image of the triangular pattern of 1T/1H phase PtSe2 on Pt(111)[87]; (c), (d) large-scale and zoom-in STM images of the periodic triangle holes in CuSe monolayer[87]; (e)–(g) scanning transmission electron microscopy image, the simulated image and atomic model of monolayer CuSe on Cu(111)[87].

    DownLoad: Full-Size Img PowerPoint

    图 11  (a) 插层硅烯纳米片段的STM图像[107]; (b) 插层单层硅烯的STM图像[107]; (c) 石墨烯/硅烯异质结构的电子局域函数计算[107]; (d) 石墨烯/硅烯异质结构的整流效应[107]

    Figure 11.  (a) STM image of the intercalated silicene nano flakes[107]; (b) STM image of the intercalated silicene monolayer[107]; (c) electron localization function calculation of the graphene/silicene heterostructure[107]; (d) rectifying effect of the graphene/silicene heterostructure[107].

    DownLoad: Full-Size Img PowerPoint

    图 12  (a), (b) Ru(0001)表面双层石墨烯/硅烯异质结构筑示意图[138]; (c), (d) 分别是硅烯插层前后的LEED图像[138]; (e), (f) 分别是硅烯插层前后的STM图像[138]; (g) Ru(0001)表面硅烯插层前后的单层石墨烯及双层石墨烯的Raman光谱对比[138]; (h) 硅烯插层后双层石墨烯的2D特征峰的分析拟合[138]

    Figure 12.  (a), (b) Schematic of the fabrication process of BLG/silicene heterostructure on Ru(0001)[138]; (c), (d) LEED patterns of BLG/Ru and BLG/silicene/Ru, respectively[138]; (e), (f) corresponding STM images for BLG/Ru and BLG/silicene/Ru, respectively[138]; (g) comparison of Raman spectra of SLG/Ru (black), SLG/silicene/Ru (green), BLG/Ru (red) and BLG/silicene/Ru (blue) [138]; (h) 2D band of BLG/silicene/Ru well fitted with four narrow Lorentzian components[138].

    DownLoad: Full-Size Img PowerPoint

    图 13  (a) 硅烯插层之后的双层石墨烯的ARPES谱[138]; (b) 优化后的起伏双层石墨烯/硅烯/Ru的原子结构模型[138]; (c) 基于图(b)中结构模型计算的能带结构, 红点组成了投影到双层石墨烯上的能带结构[138]; (d) 仅考虑来自硅烯/Ru衬底的掺杂效应时双层石墨烯的能带结构[138]; (e) 仅考虑双层石墨烯起伏/应力情况下的能带结构[138]; (f) 同时考虑掺杂和起伏/应力时双层石墨烯的能带结构[138]

    Figure 13.  (a) ARPES intensity map of the BLG after silicene intercalation[138]; (b) an optimized structure model of rippled BLG on Ru(0001) after silicene intercalation[138]; (c) calculated band structure based on the structure model in (b). The red dots are the band projected on the BLG[138]; (d) a structure model of flat BLG on silicene/Ru and the corresponding calculated band structure[138]; (e) a structure model of rippled BLG and the corresponding calculated band structure[138]; (f) a structure model of Li-doped rippled BLG and the calculated band structure[138].

    DownLoad: Full-Size Img PowerPoint

    图 14  Ru(0001)表面外延大面积、高质量石墨烯的SiO2插层及原位器件的制备 (a)—(d) SiO2插层过程及原位器件构筑示意图[108]; (e)—(g) 不同制备阶段样品的LEED表征[108]; (h) 石墨烯Hall器件的Raman mapping[108]

    Figure 14.  Synthesis of insulating SiO2 between graphene and a Ru(0001) substrate enabling electronic-device fabrication: (a)–(d) Schematic of the SiO2 intercalation and finally device fabrication processes[108]; (e)–(g) LEED patterns and corresponding structure models for sample in preparation stages (a)–(c), respectively[108]; (h) graphene G-peak intensity mapping, showing the skeleton of the graphene Hall-bar device in Fig. (d)[108].

    DownLoad: Full-Size Img PowerPoint

    图 15  (a) 薄层晶态二氧化硅插层样品的大面积截面STEM图像[108]; (b) 高分辨STEM图像显示晶态二氧化硅的双层结构[108]; (c) 界面处的EELS谱[108]; (d) 晶态二氧化硅表面石墨烯的STM图像[108]; (e) 晶态二氧化硅插层之后石墨烯的Raman光谱[108]

    Figure 15.  (a) Large-scale aberration-corrected bright-field STEM image of the bilayer-silica intercalated sample[108]; (b) high resolution STEM image taken at the red box in Fig. (a) clearly shows the atomic structure of the interfacial silica[108]; (c) EELS of Si-L2, 3 edge taken at the intercalation layer[108]; (d) atomic-resolution STM image of the graphene overlayer[108]; (e) Raman spectra of the graphene after intercalation of the crystalline SiO2[108].

    DownLoad: Full-Size Img PowerPoint

    图 16  (a) 厚层二氧化硅插层样品的界面STEM图像, 显示界面处厚层二氧化硅的厚度达到1.8 nm, 具有非晶态结构[108]; (b) X射线光电子能谱[108]; (c) 低偏压(< 10 mV)下, 对不同厚度二氧化硅插层的样品在垂直方向输运性质测试[108]; (d) 不同温度下的SdH振荡[108]; (e) 2 K下磁阻Rxx以及霍尔电阻Rxy随磁场的变化[108]; (f) 不同温度下纵向电导率在低场范围的变化规律, 与石墨烯的弱反局域理论很好的拟合[108]

    Figure 16.  (a) STEM image showing an amorphous SiO2 film with thickness of 1.8 nm between graphene and Ru substrate[108]; (b) XPS of the Si 2p and O 1s core levels; (c) vertical transport measurements at small bias (< 10 mV) for Gr/Ru, Gr/1.1 nm-silica/Ru and Gr/1.8 nm-silica/Ru samples[108]; (d) SdH oscillations at different temperatures[108]; (e) magnetoresistance Rxx and Hall resistance Rxy measured at 2 K[108]; (f) corrections of low field conductivity (△σxx) at different temperatures, showing good agreement with the weak antilocalization theory of graphene[108].

    DownLoad: Full-Size Img PowerPoint

    图 17  石墨烯“折纸术”的示意图以及STM图像[142]. 利用扫描探针显微镜针尖, 可以对石墨烯纳米岛进行折叠[142]. 利用纳米岛中的一维晶界, 可以构筑具有手性异质结构的一维碳纳米管结构[142]

    Figure 17.  Schematic and STM images of the graphene origami[142]. The graphene nanoislands can be folded by STM tip[142]. By taking advantage of the natural 1D domain boundaries in the nanoislands, heterostructure of 1D carbon nanotubes with different chirality can be constructed[142].

    DownLoad: Full-Size Img PowerPoint

    图 18  三种二维材料构筑方式的比较.

    Figure 18.  Comparison among the three construction methods of 2D materials.

    DownLoad: Full-Size Img PowerPoint
  • [1]

    Novoselov K S, Geim A K, Morozov S V, Jiang D, Zhang Y, Dubonos S V, Grigorieva I V, Firsov A A 2004 Science 306 666Google Scholar

    [2]

    Castro Neto A H, Guinea F, Peres N M R, Novoselov K S, Geim A K 2009 Rev. Mod. Phys. 81 109Google Scholar

    [3]

    Zhang X D, Xie Y 2013 Chem. Soc. Rev. 42 8187Google Scholar

    [4]

    Novoselov K S, Mishchenko A, Carvalho A, Neto A H C 2016 Science 353 aac9439Google Scholar

    [5]

    Li G, Zhang Y Y, Guo H, Huang L, Lu H L, Lin X, Wang Y L, Du S X, Gao H J 2018 Chem. Soc. Rev. 47 6073Google Scholar

    [6]

    Takeda K, Shiraishi K 1994 Phys. Rev. B 50 14916Google Scholar

    [7]

    Guzman-Verri G G, Voon L C L Y 2007 Phys. Rev. B 76 075131Google Scholar

    [8]

    Liu C C, Jiang H, Yao Y G 2011 Phys. Rev. B 84 195430Google Scholar

    [9]

    Liu C C, Feng W X, Yao Y G 2011 Phys. Rev. Lett. 107 076802Google Scholar

    [10]

    Lalmi B, Oughaddou H, Enriquez H, Kara A, Vizzini S, Ealet B, Aufray B 2010 Appl. Phys. Lett. 97 223109Google Scholar

    [11]

    Vogt P, De Padova P, Quaresima C, Avila J, Frantzeskakis E, Asensio M C, Resta A, Ealet B, Le Lay G 2012 Phys. Rev. Lett. 108 155501Google Scholar

    [12]

    Feng B, Ding Z, Meng S, Yao Y, He X, Cheng P, Chen L, Wu K 2012 Nano Lett. 12 3507Google Scholar

    [13]

    Lin C L, Arafune R, Kawahara K, Tsukahara N, Minamitani E, Kim Y, Takagi N, Kawai M 2012 Appl. Phys. Express 5 045802Google Scholar

    [14]

    Onoda J, Yabuoshi K, Miyazaki H, Sugimoto Y 2017 Phys. Rev. B 96 241302Google Scholar

    [15]

    Lin C L, Arafune R, Kawahara K, Kanno M, Tsukahara N, Minamitani E, Kim Y, Kawai M, Takagi N 2013 Phys. Rev. Lett. 110 076801Google Scholar

    [16]

    Feng Y, Liu D F, Feng B J, Liu X, Zhao L, Xie Z J, Liu Y, Liang A J, Hu C, Hu Y, He S L, Liu G D, Zhang J, Chen C T, Xu Z Y, Chen L, Wu K H, Liu Y T, Lin H, Huang Z Q, Hsu C H, Chuang F C, Bansil A, Zhou X J 2016 Proc. Natl. Acad. Sci. U. S. A. 113 14656Google Scholar

    [17]

    Fleurence A, Friedlein R, Ozaki T, Kawai H, Wang Y, Yamada-Takamura Y 2012 Phys. Rev. Lett. 108 245501Google Scholar

    [18]

    Meng L, Wang Y L, Zhang L Z, Du S X, Wu R T, Li L F, Zhang Y, Li G, Zhou H T, Hofer W A, Gao H J 2013 Nano Lett. 13 685Google Scholar

    [19]

    Huang L, Zhang Y F, Zhang Y Y, Xu W Y, Que Y D, Li E, Pan J B, Wang Y L, Liu Y Q, Du S X, Pantelides S T, Gao H J 2017 Nano Lett. 17 1161Google Scholar

    [20]

    Brumfiel G 2013 Nature 495 152Google Scholar

    [21]

    De Padova P, Ottaviani C, Quaresima C, Olivieri B, Imperatori P, Salomon E, Angot T, Quagliano L, Romano C, Vona A, Muniz-Miranda M, Generosi A, Paci B, Le Lay G 2014 2 D Mater. 1 021003
    [22]

    Du Y, Zhuang J C, Wang J O, Li Z, Liu H, Zhao J, Xu X, Feng H, Chen L, Wu K, Wang X, Dou S X 2016 Sci. Adv. 2 e1600067Google Scholar

    [23]

    Tao L, Cinquanta E, Chiappe D, Grazianetti C, Fanciulli M, Dubey M, Molle A, Akinwande D 2015 Nat. Nanotechnol. 10 227Google Scholar

    [24]

    Li L F, Lu S Z, Pan J B, Qin Z H, Wang Y Q, Wang Y L, Cao G Y, Du S X, Gao H J 2014 Adv. Mater. 26 4820Google Scholar

    [25]

    Qin Z H, Pan J B, Lu S Z, Yan S, Wang Y L, Du S X, Gao H J, Cao G Y 2017 Adv. Mater. 29 1606046Google Scholar

    [26]

    Acun A, Zhang L, Bampoulis P, Farmanbar M, van Houselt A, Rudenko A N, Lingenfelder M, Brocks G, Poelsema B, Katsnelson M I, Zandvliet H J W 2015 J. Phys. Condens. Matter 27 442001
    [27]

    Davila M E, Xian L, Cahangirov S, Rubio A, Le Lay G 2014 New J. Phys. 16 095002Google Scholar

    [28]

    Derivaz M, Dentel D, Stephan R, Hanf M C, Mehdaoui A, Sonnet P, Pirri C 2015 Nano Lett. 15 2510Google Scholar

    [29]

    Zhang L, Bampoulis P, Rudenko A N, Yao Q, van Houselt A, Poelsema B, Katsnelson M I, Zandvliet H J W 2016 Phys. Rev. Lett. 116 256804Google Scholar

    [30]

    Lin C H, Huang A, Pai W W, Chen W C, Chen T Y, Chang T R, Yukawa R, Cheng C M, Mou C Y, Matsuda I, Chiang T C, Jeng H T, Tang S J 2018 Phys. Rev. Mater. 2 024003Google Scholar

    [31]

    Chou B H, Huang Z Q, Hsu C H, Chuang F C, Liu Y T, Lin H, Bansil A 2014 New J. Phys. 16 115008Google Scholar

    [32]

    Zhu F F, Chen W J, Xu Y, Gao C L, Guan D D, Liu C H, Qian D, Zhang S C, Jia J F 2015 Nat. Mater. 14 1020Google Scholar

    [33]

    Xu C Z, Chan Y H, Chen P, Wang X X, Flototto D, Hlevyack J A, Bian G, Mo S K, Chou M Y, Chiang T C 2018 Phys. Rev. B 97 035122Google Scholar

    [34]

    Zang Y Y, Jiang T, Gong Y, Guan Z Y, Liu C, Liao M H, Zhu K J, Li Z, Wang L L, Li W, Song C L, Zhang D, Xu Y, He K, Ma X C, Zhang S C, Xue Q K 2018 Adv. Funct. Mater. 28 1802723Google Scholar

    [35]

    Xu C Z, Chan Y H, Chen Y G, Chen P, Wang X X, Dejoie C, Wong M H, Hlevyack J A, Ryu H J, Kee H Y, Tamura N, Chou M Y, Hussain Z, Mo S K, Chiang T C 2017 Phys. Rev. Lett. 118 146402Google Scholar

    [36]

    Zheng X H, Zhang J F, Tong B, Du R R 2020 2 D Mater. 7 011001
    [37]

    Deng J L, Xia B Y, Ma X C, Chen H Q, Shan H, Zhai X F, Li B, Zhao A D, Xu Y, Duan W H, Zhang S C, Wang B, Hou J G 2018 Nat. Mater. 17 1081Google Scholar

    [38]

    Yuhara J, Fujii Y, Nishino K, Isobe N, Nakatake M, Xian L D, Rubio A, Le Lay G 2018 2 D Mater. 5 025002
    [39]

    Yuhara J, Le Lay G 2020 Jpn. J. Appl. Phys. 59 SN0801Google Scholar

    [40]

    Dong X, Zhang L Z, Yoon M N, Zhang P P 2021 2 D Mater. 8 045003
    [41]

    Yu X L, Huang L, Wu J S 2017 Phys. Rev. B 95 125113Google Scholar

    [42]

    Huang Z Q, Hsu C H, Chuang F C, Liu Y T, Lin H, Su W S, Ozolins V, Bansil A 2014 New J. Phys. 16 105018Google Scholar

    [43]

    Yu X L, Wu J S 2018 Phys. Chem. Chem. Phys. 20 2296Google Scholar

    [44]

    Rivero P, Yan J A, Garcia-Suarez V M, Ferrer J, Barraza-Lopez S 2014 Phys. Rev. B 90 241408(R)
    [45]

    Kim J, Qin S Y, Yao W, Niu Q, Chou M Y, Shih C K 2010 Proc. Natl. Acad. Sci. U. A. S. 107 12761Google Scholar

    [46]

    Zhang T, Cheng P, Li W J, Sun Y J, Wang G, Zhu X G, He K, Wang L L, Ma X C, Chen X, Wang Y Y, Liu Y, Lin H Q, Jia J F, Xue Q K 2010 Nat. Phys. 6 104Google Scholar

    [47]

    Brun C, Cren T, Cherkez V, Debontridder F, Pons S, Fokin D, Tringides M C, Bozhko S, Ioffe L B, Altshuler B L, Roditchev D 2014 Nat. Phys. 10 444Google Scholar

    [48]

    Roditchev D, Brun C, Serrier-Garcia L, Cuevas J C, Bessa V H L, Milosevic M V, Debontridder F, Stolyarov V, Cren T 2015 Nat. Phys. 11 332Google Scholar

    [49]

    Yuhara J, He B J, Matsunami N, Nakatake M, Le Lay G 2019 Adv. Mater. 31 1901017Google Scholar

    [50]

    Bihlmayer G, Sassmannshausen J, Kubetzka A, Blugel S, von Bergmann K, Wiesendanger R 2020 Phys. Rev. Lett. 124 126401Google Scholar

    [51]

    Liu H S, Gao J F, Zhao J J 2013 Sci. Rep. 3 3238Google Scholar

    [52]

    Liu Y Y, Penev E S, Yakobson B I 2013 Angew. Chem. Int. Ed. 52 3156Google Scholar

    [53]

    Mannix A J, Zhou X F, Kiraly B, Wood J D, Alducin D, Myers B D, Liu X L, Fisher B L, Santiago U, Guest J R, Yacaman M J, Ponce A, Oganov A R, Hersam M C, Guisinger N P 2015 Science 350 1513Google Scholar

    [54]

    Feng B J, Zhang J, Zhong Q, Li W B, Li S, Li H, Cheng P, Meng S, Chen L, Wu K H 2016 Nat. Chem. 8 564
    [55]

    Chen C Y, Lü H F, Zhang P, Zhuo Z W, Wang Y, Ma C, Li W B, Wang X G, Feng B J, Cheng P, Wu X J, Wu K H, Chen L 2021 Nat. Chem. 14 25
    [56]

    Liu X L, Li Q C, Ruan Q Y, Rahn M S, Yakobson B I, Hersam M C 2021 Nat. Mater. 21 35
    [57]

    Xia F N, Wang H, Jia Y C 2014 Nat. Commun. 5 4458Google Scholar

    [58]

    Carvalho A, Wang M, Zhu X, Rodin A S, Su H B, Neto A H C 2016 Nat. Rev. Mater. 1 16061Google Scholar

    [59]

    Akhtar M, Anderson G, Zhao R, Alruqi A, Mroczkowska J E, Sumanasekera G, Jasinski J B 2017 NPJ 2D Mater. Appl. 1 5Google Scholar

    [60]

    Zhang J L, Zhao S T, Han C, Wang Z Z, Zhong S, Sun S, Guo R, Zhou X, Gu C D, Di Yuan K, Li Z Y, Chen W 2016 Nano Lett. 16 4903Google Scholar

    [61]

    Zhu Z, Tomanek D 2014 Phys. Rev. Lett. 112 176802Google Scholar

    [62]

    Wu X, Shao Y, Liu H, Feng Z, Wang Y L, Sun J T, Liu C, Wang J O, Liu Z L, Zhu S Y, Wang Y Q, Du S X, Shi Y G, Ibrahim K, Gao H J 2017 Adv. Mater. 29 1605407Google Scholar

    [63]

    Zhu S Y, Shao Y, Wang E, Cao L, Li X Y, Liu Z L, Liu C, Liu L W, Wang J O, Ibrahim K, Sun J T, Wang Y L, Du S X, Gao H J 2019 Nano Lett. 19 6323Google Scholar

    [64]

    Shao Y, Liu Z L, Cheng C, Wu X, Liu H, Liu C, Wang J O, Zhu S Y, Wang Y Q, Shi D X, Ibrahim K, Sun J T, Wang Y L, Gao H J 2018 Nano Lett. 18 2133Google Scholar

    [65]

    Reis F, Li G, Dudy L, Bauernfeind M, Glass S, Hanke W, Thomale R, Schafer J, Claessen R 2017 Science 357 287Google Scholar

    [66]

    Li L F, Wang Y L, Xie S Y, Li X B, Wang Y Q, Wu R T, Sun H B, Zhang S B, Gao H J 2013 Nano Lett. 13 4671Google Scholar

    [67]

    Gao H J, Gao L 2010 Prog. Surf. Sci. 85 28Google Scholar

    [68]

    Gao H J, Xue Z Q, Wang K Z, Wu Q D, Pang S 1996 Appl. Phys. Lett. 68 2192Google Scholar

    [69]

    Gao H J, Sohlberg K, Xue Z Q, Chen H Y, Hou S M, Ma L P, Fang X W, Pang S J, Pennycook S J 2000 Phys. Rev. Lett. 84 1780Google Scholar

    [70]

    Feng M, Guo X F, Lin X, He X B, Ji W, Du S X, Zhang D Q, Zhu D B, Gao H J 2005 J. Am. Chem. Soc. 127 15338Google Scholar

    [71]

    Feng M, Gao L, Deng Z T, Ji W, Guo X F, Du S X, Shi D X, Zhang D Q, Zhu D B, Gao H J 2007 J. Am. Chem. Soc. 129 2204Google Scholar

    [72]

    Du S X, Gao H J, Seidel C, Tsetseris L, Ji W, Kopf H, Chi L F, Fuchs H, Pennycook S J, Pantelides S T 2006 Phys. Rev. Lett. 97 156105Google Scholar

    [73]

    Shi D, Ji W, Lin X, He X, Lian J, Gao L, Cai J, Lin H, Du S, Lin F, Seidel C, Chi L, Hofer W, Fuchs H, Gao H J 2006 Phys. Rev. Lett. 96 226101Google Scholar

    [74]

    Zhang S, Song Y, Li H, Li J M, Qian K, Liu C, Wang J O, Qian T, Zhang Y Y, Lu J C, Ding H, Lin X, Pan J B, Du S X, Gao H J 2020 Chin. Phys. Lett. 37 068103Google Scholar

    [75]

    Zheng C, Zhao D P, Cai X Q, Huang W T, Meng F Q, Zhang Q H, Tang L, Hu X P, Gu L, Ji S H, Chen X 2020 Chin. Phys. Lett. 37 087401Google Scholar

    [76]

    王兴悦, 张辉, 阮子林, 郝振亮, 杨孝天, 蔡金明, 卢建臣 2020 物理学报 69 118101Google Scholar

    Wang X Y, Zhang H, Ruan Z L, Hao Z L, Yang X T, Cai J M, Lu J C 2020 Acta Phys. Sin. 69 118101Google Scholar

    [77]

    Lu J C, Bao D L, Qian K, Zhang S, Chen H, Lin X, Du S X, Gao H J 2017 ACS Nano 11 1689Google Scholar

    [78]

    Lu J C, Niu G F, Ren X, Bao D L, Chen H, Yang H T, Lin X, Du S X, Gao H J 2021 Nanoscale 13 19165Google Scholar

    [79]

    Kezilebieke S, Huda N, Vano V, Aapro M, Ganguli S C, Silveira O J, Glodzik S, Foster A S, Ojanen T, Liljeroth P 2020 Nature 588 424Google Scholar

    [80]

    Li E, Zhang R Z, Li H, Liu C, Li G, Wang J O, Qian T, Ding H, Zhang Y Y, Du S X, Lin X, Gao H J 2018 Chin. Phys. B 27 086804Google Scholar

    [81]

    Ugeda M M, Bradley A J, Shi S F, da Jornada F H, Zhang Y, Qiu D Y, Ruan W, Mo S K, Hussain Z, Shen Z X, Wang F, Louie S G, Crommie M F 2014 Nat. Mater. 13 1091Google Scholar

    [82]

    Li E, Wang D F, Fan P, Zhang R Z, Zhang Y Y, Li G, Mao J H, Wang Y L, Lin X, Du S X, Gao H J 2018 Nano Res. 11 5858Google Scholar

    [83]

    Fan P, Zhang R Z, Qi J, Li E, Qian G J, Chen H, Wang D F, Zheng Q, Wang Q, Lin X, Zhang Y Y, Du S X, Hofer W A, Gao H J 2020 Chin. Phys. B 29 098102Google Scholar

    [84]

    Fan P, Qian G J, Wang D F, Li E, Wang Q, Chen H, Lin X, Gao H J 2021 Chin. Phys. B 30 018105Google Scholar

    [85]

    Wang Y L, Li L F, Yao W, Song S R, Sun J T, Pan J B, Ren X, Li C, Okunishi E, Wang Y Q, Wang E Y, Shao Y, Zhang Y Y, Yang H T, Schwier E F, Iwasawa H, Shimada K, Taniguchi M, Cheng Z H, Zhou S Y, Du S X, Pennycook S J, Pantelides S T, Gao H J 2015 Nano Lett. 15 4013Google Scholar

    [86]

    Wang Y Q, Wu X, Wang Y L, Shao Y, Lei T, Wang J O, Zhu S Y, Guo H M, Zhao L X, Chen G F, Nie S M, Weng H M, Ibrahim K, Dai X, Fang Z, Gao H J 2016 Adv. Mater. 28 5013Google Scholar

    [87]

    Lin X, Lu J C, Shao Y, Zhang Y Y, Wu X, Pan J B, Gao L, Zhu S Y, Qian K, Zhang Y F, Bao D L, Li L F, Wang Y Q, Liu Z L, Sun J T, Lei T, Liu C, Wang J O, Ibrahim K, Leonard D N, Zhou W, Guo H M, Wang Y L, Du S X, Pantelides S T, Gao H J 2017 Nat. Mater. 16 717Google Scholar

    [88]

    Gao L, Sun J T, Lu J C, Li H, Qian K, Zhang S, Zhang Y Y, Qian T, Ding H, Lin X, Du S, Gao H J 2018 Adv. Mater. 30 1707055Google Scholar

    [89]

    Dong L, Wang A W, Li E, Wang Q, Li G, Huan Q, Gao H J 2019 Chin. Phys. Lett. 36 028102Google Scholar

    [90]

    Wang A W, Liu Z Y, Pan J B, Li Q C, Li G, Huan Q, Du S X, Gao H J 2020 Chin. Phys. B 29 078102Google Scholar

    [91]

    Qian K, Gao L, Chen X Y, Li H, Zhang S, Zhang X L, Zhu S Y, Yan J H, Bao D L, Cao L, Shi J A, Lu J C, Liu C, Wang J, Qian T, Ding H, Gu L, Zhou W, Zhang Y Y, Lin X, Du S X, Ouyang M, Pantelides S T, Gao H J 2020 Adv. Mater. 32 1908314Google Scholar

    [92]

    Li S H, Gu G X, Liu E K, Cheng P, Feng B J, Li Y Q, Chen L, Wu K H 2020 ACS Appl. Electron. Mater. 2 126Google Scholar

    [93]

    Gong Y, Guo J W, Li J H, Zhu K J, Liao M H, Liu X Z, Zhang Q H, Gu L, Tang L, Feng X, Zhang D, Li W, Song C L, Wang L L, Yu P, Chen X, Wang Y Y, Yao H, Duan W H, Xu Y, Zhang S C, Ma X C, Xue Q K, He K 2019 Chin. Phys. Lett. 36 076801Google Scholar

    [94]

    Wang Q Y, Li Z, Zhang W H, Zhang Z C, Zhang J S, Li W, Ding H, Ou Y B, Deng P, Chang K, Wen J, Song C L, He K, Jia J F, Ji S H, Wang Y Y, Wang L L, Chen X, Ma X C, Xue Q K 2012 Chin. Phys. Lett. 29 037402Google Scholar

    [95]

    Chang K, Deng P, Zhang T, Lin H C, Zhao K, Ji S H, Wang L L, He K, Ma X C, Chen X, Xue Q K 2015 EPL 109 28003Google Scholar

    [96]

    Sakoda M, Iida K, Naito M 2018 Supercond. Sci. Technol. 31 093001Google Scholar

    [97]

    Li Z, Sang L N, Liu P, Yue Z J, Fuhrer M S, Xue Q K, Wang X L 2021 Small 17 1904788Google Scholar

    [98]

    Zhang Y, He K, Chang C Z, Song C L, Wang L L, Chen X, Jia J F, Fang Z, Dai X, Shan W Y, Shen S Q, Niu Q, Qi X L, Zhang S C, Ma X C, Xue Q K 2010 Nat. Phys. 6 584Google Scholar

    [99]

    Sun H H, Zhang K W, Hu L H, Li C, Wang G Y, Ma H Y, Xu Z A, Gao C L, Guan D D, Li Y Y, Liu C H, Qian D, Zhou Y, Fu L, Li S C, Zhang F C, Jia J F 2016 Phys. Rev. Lett. 116 257003Google Scholar

    [100]

    Loffler D, Uhlrich J J, Baron M, Yang B, Yu X, Lichtenstein L, Heinke L, Buchner C, Heyde M, Shaikhutdinov S, Freund H J, Wlodarczyk R, Sierka M, Sauer J 2010 Phys. Rev. Lett. 105 146104Google Scholar

    [101]

    Liang Y, Chen Y J, Sun Y W, Xu S P, Wu J X, Tan C W, Xu X F, Yuan H T, Yang L X, Chen Y L, Gao P, Guo J D, Peng H L 2019 Adv. Mater. 31 1901964Google Scholar

    [102]

    Mao J H, Huang L, Pan Y, Gao M, He J F, Zhou H T, Guo H M, Tian Y, Zou Q, Zhang L Z, Zhang H G, Wang Y L, Du S X, Zhou X J, Castro Neto A H, Gao H J 2012 Appl. Phys. Lett. 100 093101Google Scholar

    [103]

    Li L F, Wang Y L, Meng L, Wu R T, Gao H J 2013 Appl. Phys. Lett. 102 093106Google Scholar

    [104]

    Huang L, Pan Y, Pan L D, Gao M, Xu W Y, Que Y D, Zhou H T, Wang Y L, Du S X, Gao H J 2011 Appl. Phys. Lett. 99 163107Google Scholar

    [105]

    Li G, Zhou H T, Pan L D, Zhang Y, Huang L, Xu W Y, Du S X, Ouyang M, Ferrari A C, Gao H J 2015 J. Am. Chem. Soc. 137 7099Google Scholar

    [106]

    Que Y D, Zhang Y, Wang Y L, Huang L, Xu W Y, Tao J, Wu L J, Zhu Y M, Kim K, Weinl M, Schreck M, Shen C M, Du S X, Liu Y Q, Gao H J 2015 Adv. Mater. Interfaces 2 1400543Google Scholar

    [107]

    Li G, Zhang L Z, Xu W Y, Pan J B, Song S R, Zhang Y, Zhou H T, Wang Y L, Bao L H, Zhang Y Y, Du S X, Ouyang M, Pantelides S T, Gao H J 2018 Adv. Mater. 30 1804650Google Scholar

    [108]

    Guo H, Wang X Y, Huang L, Jin X, Yang Z Z, Zhou Z, Hu H, Zhang Y Y, Lu H L, Zhang Q H, Shen C M, Lin X, Gu L, Dai Q, Bao L H, Du S X, Hofer W, Pantelides S T, Gao H J 2020 Nano Lett. 20 8584Google Scholar

    [109]

    Enderlein C, Kim Y S, Bostwick A, Rotenberg E, Horn K 2010 New J. Phys. 12 033014Google Scholar

    [110]

    Riedl C, Coletti C, Iwasaki T, Zakharov A A, Starke U 2009 Phys. Rev. Lett. 103 246804Google Scholar

    [111]

    Jin L, Fu Q, Mu R T, Tan D L, Bao X H 2011 Phys. Chem. Chem. Phys. 13 16655Google Scholar

    [112]

    Feng X F, Maier S, Salmeron M 2012 J. Am. Chem. Soc. 134 5662Google Scholar

    [113]

    Lu J, Neto A H C, Loh K P 2012 Nat. Commun. 3 823Google Scholar

    [114]

    Mu R T, Fu Q, Jin L, Yu L, Fang G Z, Tan D L, Bao X H 2012 Angew. Chem. Int. Ed. 51 4856Google Scholar

    [115]

    Sicot M, Leicht P, Zusan A, Bouvron S, Zander O, Weser M, Dedkov Y S, Horn K, Fonin M 2012 ACS Nano 6 151Google Scholar

    [116]

    Decker R, Brede J, Atodiresei N, Caciuc V, Blugel S, Wiesendanger R 2013 Phys. Rev. B 87 041403
    [117]

    Petrovic M, Rakic I S, Runte S, Busse C, Sadowski J T, Lazic P, Pletikosic I, Pan Z H, Milun M, Pervan P, Atodiresei N, Brako R, Sokcevic D, Valla T, Michely T, Kralj M 2013 Nat. Commun. 4 2772Google Scholar

    [118]

    Al Balushi Z Y, Wang K, Ghosh R K, Vila R A, Eichfeld S M, Caldwell J D, Qin X Y, Lin Y C, DeSario P A, Stone G, Subramanian S, Paul D F, Wallace R M, Datta S, Redwing J M, Robinson J A 2016 Nat. Mater. 15 1166Google Scholar

    [119]

    Sutter P, Sadowski J T, Sutter E A 2010 J. Am. Chem. Soc. 132 8175Google Scholar

    [120]

    Xia C, Watcharinyanon S, Zakharov A A, Yakimova R, Hultman L, Johansson L I, Virojanadara C 2012 Phys. Rev. B 85 045418Google Scholar

    [121]

    Pan Y, Shi D X, Gao H J 2007 Chin. Phys. 16 3151Google Scholar

    [122]

    Pan Y, Zhang H G, Shi D X, Sun J T, Du S X, Liu F, Gao H J 2009 Adv. Mater. 21 2777Google Scholar

    [123]

    Cui Y, Gao J F, Jin L, Zhao J J, Tan D L, Fu Q, Bao X H 2012 Nano Res. 5 352Google Scholar

    [124]

    Cao Y, Fatemi V, Fang S, Watanabe K, Taniguchi T, Kaxiras E, Jarillo-Herrero P 2018 Nature 556 43Google Scholar

    [125]

    Cao Y, Fatemi V, Demir A, Fang S, Tomarken S L, Luo J Y, Sanchez-Yamagishi J D, Watanabe K, Taniguchi T, Kaxiras E, Ashoori R C, Jarillo-Herrero P 2018 Nature 556 80Google Scholar

    [126]

    Andrei E Y, MacDonald A H 2020 Nat. Mater. 19 1265Google Scholar

    [127]

    Castro E V, Novoselov K S, Morozov S V, Peres N M R, Dos Santos J M B L, Nilsson J, Guinea F, Geim A K, Castro Neto A H 2007 Phys. Rev. Lett. 99 216802Google Scholar

    [128]

    Zhang Y B, Tang T T, Girit C, Hao Z, Martin M C, Zettl A, Crommie M F, Shen Y R, Wang F 2009 Nature 459 820Google Scholar

    [129]

    Oostinga J B, Heersche H B, Liu X L, Morpurgo A F, Vandersypen L M K 2008 Nat. Mater. 7 151Google Scholar

    [130]

    Mak K F, Lui C H, Shan J, Heinz T F 2009 Phys. Rev. Lett. 102 256405Google Scholar

    [131]

    Choi S M, Jhi S H, Son Y W 2010 Nano Lett. 10 3486Google Scholar

    [132]

    Ohta T, Bostwick A, Seyller T, Horn K, Rotenberg E 2006 Science 313 951Google Scholar

    [133]

    Samuels A J, Carey J D 2013 ACS Nano 7 2790Google Scholar

    [134]

    Zhang W J, Lin C T, Liu K K, Tite T, Su C Y, Chang C H, Lee Y H, Chu C W, Wei K H, Kuo J L, Li L J 2011 ACS Nano 5 7517Google Scholar

    [135]

    Tian X Q, Xu J B, Wang X M 2010 J. Phys. Chem. B 114 11377Google Scholar

    [136]

    Wang Y Y, Ni Z Y, Liu Q H, Quhe R G, Zheng J X, Ye M, Yu D P, Shi J J, Yang J B, Li J, Lu J 2015 Adv. Funct. Mater. 25 68Google Scholar

    [137]

    Guo H, Wang X Y, Lu H L, Bao L H, Peng H, Qian K, Ma J J, Li G, Huang L, Lin X, Zhang Y Y, Du S X, Pantelides S T, Gao H J 2019 2 D Mater. 6 045044
    [138]

    Guo H, Zhang R Z, Li H, Wang X Y, Lu H L, Qian K, Li G, Huang L, Lin X, Zhang Y Y, Ding H, Du S X, Pantelides S T, Gao H J 2020 Nano Lett. 20 2674Google Scholar

    [139]

    Dahal A, Batzill M 2015 Sci. Rep. 5 11378Google Scholar

    [140]

    Picone A, Giannotti D, Finazzi M, Duo L, Ciccacci F, Brambilla A 2017 J. Phys. Chem. C 121 16803Google Scholar

    [141]

    Wang X Y, Guo H, Lu J C, Lu H L, Lin X, Shen C M, Bao L H, Du S X, Gao H J 2021 Chin. Phys. B 30 048102Google Scholar

    [142]

    Chen H, Zhang X L, Zhang Y Y, Wang D F, Bao D L, Que Y D, Xiao W D, Du S X, Ouyang M, Pantelides S T, Gao H J 2019 Science 365 1036Google Scholar

  • [1] You Ming-Hui, Li Xue, Li Shi-Jun, Liu Guo-Jun. Growth of lattice matched InAs/AlSb superlattices by molecular beam epitaxy. Acta Physica Sinica, 2023, 72(1): 014203. doi: 10.7498/aps.72.20221383
    [2] Zheng Xiao-Hu, Zhang Jian-Feng, Du Rui-Rui. Comparative study on epitaxial growth of stanene and bismuthene on InSb(111) substrate. Acta Physica Sinica, 2022, 71(18): 186401. doi: 10.7498/aps.71.20221024
    [3] Li Pei-Gen, Zhang Ji-Hai, Tao Ye, Zhong Ding-Yong. Two-dimensional magnetic transition metal halides: molecular beam epitaxy growth and physical property modulation. Acta Physica Sinica, 2022, 71(12): 127505. doi: 10.7498/aps.71.20220727
    [4] Guo Qin-Min, Qin Zhi-Hui. Development and application of vapor deposition technology in atomic manufacturing. Acta Physica Sinica, 2021, 70(2): 028101. doi: 10.7498/aps.70.20201436
    [5] Wang Xing-Yue, Zhang Hui, Ruan Zi-Lin, Hao Zhen-Liang, Yang Xiao-Tian, Cai Jin-Ming, Lu Jian-Chen. Research progress of monolayer two-dimensional atomic crystal materials grown by molecular beam epitaxy in ultra-high vacuum conditions. Acta Physica Sinica, 2020, 69(11): 118101. doi: 10.7498/aps.69.20200174
    [6] Huang Li, Li Geng, Zhang Yu-Yang, Bao Li-Hong, Huan Qing, Lin Xiao, Wang Ye-Liang, Guo Hai-Ming, Shen Cheng-Min, Du Shi-Xuan, Gao Hong-Jun. Construction, physical properties and applications of low-dimensional atomic/molecular crystals. Acta Physica Sinica, 2018, 67(12): 126801. doi: 10.7498/aps.67.20180846
    [7] Xiao Jia-Xing, Lu Jun, Zhu Li-Jun, Zhao Jian-Hua. Perpendicular magnetic properties of ultrathin L10-Mn1.67Ga films grown by molecular-beam epitaxy. Acta Physica Sinica, 2016, 65(11): 118105. doi: 10.7498/aps.65.118105
    [8] Zhang Ma-Lin, Ge Jian-Feng, Duan Ming-Chao, Yao Gang, Liu Zhi-Long, Guan Dan-Dan, Li Yao-Yi, Qian Dong, Liu Can-Hua, Jia Jin-Feng. Molecular beam epitaxy growth of multilayer FeSe thin film on SrTiO3 (001). Acta Physica Sinica, 2016, 65(12): 127401. doi: 10.7498/aps.65.127401
    [9] Liu Ke, Ma Wen-Quan, Huang Jian-Liang, Zhang Yan-Hua, Cao Yu-Lian, Huang Wen-Jun, Zhao Cheng-Cheng. Three-color InAs/GaAs quantum dot infrared photodetector with AlGaAs inserting layer. Acta Physica Sinica, 2016, 65(10): 108502. doi: 10.7498/aps.65.108502
    [10] Yang Wen-Xian, Ji Lian, Dai Pan, Tan Ming, Wu Yuan-Yuan, Lu Jian-Ya, Li Bao-Ji, Gu Jun, Lu Shu-Long, Ma Zhong-Quan. Study on photoluminescence properties of 1.05 eV InGaAsP layers grown by molecular beam epitaxy. Acta Physica Sinica, 2015, 64(17): 177802. doi: 10.7498/aps.64.177802
    [11] Zhu Meng-Yao, Lu Jun, Ma Jia-Lin, Li Li-Xia, Wang Hai-Long, Pan Dong, Zhao Jian-Hua. Molecular-beam epitaxy of high-quality diluted magnetic semiconductor (Ga, Mn)Sb single-crystalline films. Acta Physica Sinica, 2015, 64(7): 077501. doi: 10.7498/aps.64.077501
    [12] Li Jing-Cheng, Zhao Ai-Di, Wang Bing. Controlling the electronic states and transport properties of single cobalt(Ⅱ)octaethylporphyrin molecule adsorbed on Au(111) surface. Acta Physica Sinica, 2015, 64(7): 076803. doi: 10.7498/aps.64.076803
    [13] Wang Meng, Ou Yun-Bo, Li Fang-Sen, Zhang Wen-Hao, Tang Chen-Jia, Wang Li-Li, Xue Qi-Kun, Ma Xu-Cun. Molecular beam epitaxy of single unit-cell FeSe superconducting films on SrTiO3(001). Acta Physica Sinica, 2014, 63(2): 027401. doi: 10.7498/aps.63.027401
    [14] Han Wen-Peng, Shi Yan-Meng, Li Xiao-Li, Luo Shi-Qiang, Lu Yan, Tan Ping-Heng. The numerical-aperture-dependent optical contrast and thickness determination of ultrathin flakes of two-dimensional atomic crystals: A case of graphene multilayers. Acta Physica Sinica, 2013, 62(11): 110702. doi: 10.7498/aps.62.110702
    [15] Su Shao-Jian, Wang Wei, Zhang Guang-Ze, Hu Wei-Xuan, Bai An-Qi, Xue Chun-Lai, Zuo Yu-Hua, Cheng Bu-Wen, Wang Qi-Ming. Epitaxial growth of Ge0.975Sn0.025alloy films on Si(001) substrates by molecular beam epitaxy. Acta Physica Sinica, 2011, 60(2): 028101. doi: 10.7498/aps.60.028101
    [16] Ding Zhao, Wei Jun, Yang Zai-Rong, Luo Zi-Jiang, He Ye-Quan, Zhou Xun, He Hao, Deng Chao-Yong. Study on temperature calibration and surface phase transition of GaAs crystal substrate in MBE growth by RHEED real-time monitoring. Acta Physica Sinica, 2011, 60(1): 016109. doi: 10.7498/aps.60.016109
    [17] Zhao Ming-Hai, Sun Jing-Jing, Wang Dan, Zou Zhi-Qiang, Liang Qi. STM studies of the epitaxial growth of C60 molecules on Si(111)-7×7 surface. Acta Physica Sinica, 2010, 59(1): 636-642. doi: 10.7498/aps.59.636
    [18] Zhang Yan-Hui, Chen Ping-Ping, Li Tian-Xin, Yin Hao. InNSb single crystal films prepared on GaAs (001) substrates by molecular beam epitaxy. Acta Physica Sinica, 2010, 59(11): 8026-8030. doi: 10.7498/aps.59.8026
    [19] Chang Jun, Li Hua, Han Ying-Jun, Tan Zhi-Yong, Cao Jun-Cheng. Material growth and characterization of terahertz quantum-cascade lasers. Acta Physica Sinica, 2009, 58(10): 7083-7087. doi: 10.7498/aps.58.7083
    [20] JING CHAO, JIN XIAO-FENG, DONG GUO-SHENG, GONG XIAO-YAN, YU LI-MING, ZHENG WEI-MIN. EXCHANGE BIASING IN MOLECULAR-BEAM-EPITAXY-GROWN Fe/Fe50Mn50 BILAYERS. Acta Physica Sinica, 2000, 49(10): 2022-2026. doi: 10.7498/aps.49.2022
Catalog
Metrics
  • Abstract views:  9292
  • PDF Downloads:  498
Publishing process
  • Received Date:  28 December 2021
  • Accepted Date:  22 January 2022
  • Available Online:  10 February 2022
  • Published Online:  20 May 2022

/

返回文章
返回

Authors

Referees

About Journal

About

Copyright ©Acta Physica Sinica All Rights Reserved. 京ICP备05002789号-1

Address： PostCode：100190

Phone：010-82649829，82649241,82649863 Email：apsoffice@iphy.ac.cn   百度统计