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通过考虑构筑在半导体GaAs/AlxGa1-xAs异质结上的磁受限半导体纳米结构中的塞曼效应和自旋-轨道耦合，本文采用理论分析和数值计算相结合的方法研究了电子的传输时间与自旋极化。利用矩阵对角化和改进的转移矩阵方法，数值求解电子的薛定谔方程；采用H.G.Winful理论求电子的居留时间，并计算自旋极化率。由于塞曼效应与自旋-轨道耦合，电子的居留时间明显地与其自旋有关，因此可在时间维度上分离自旋、实现半导体中电子的自旋极化。因为半导体GaAs的有效g-因子很小，电子自旋极化主要源于自旋-轨道耦合，大约为塞曼效应引起的自旋极化的四倍。由于电子的有效势与自旋-轨道耦合的强度有关，电子的居留时间及其自旋极化可通过界面限制电场或应力工程进行有效调控。这些有趣的结果不仅对半导体自旋注入具有参考价值，而且还可为半导体自旋电子学器件应用提供时间电子自旋分裂器。
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关键词:
- 半导体自旋电子学 /
- 磁调制半导体纳米结构 /
- 自旋-轨道耦合 /
- 居留时间
Because digital information in semiconductor spintronics is encoded,stored,processed,and transferred by electron spins instead of its charge,the operation of a spintronic device requires that electrons in semiconductors are spin polarized.But spin states of electrons in traditional semiconductor materials are usually degenerate,therefore,conventional semiconductors cannot are directly exploited to design spintronic devices.Thus,how to spin polarized electrons in ordinary semiconductors (also called spin injection) including its effective manipulation has become an important direction of research.In physics,either Zeeman effect between electron spins and external magnetic fields or spin-orbit coupling of electron spins and its spatial momentums can be employed to achieve electron-spin polarization.According to these physical mechanisms,some effective schemes have been developed successfully,such as spin filtering,temporally separating electron-spins,spatial separations of electron spins,and so on.Utilizing theoretical analysis combined with numerical calculation,transmission time is investigated by considering both Zeeman effect as well as Rashba and Dresselhaus spin-orbit couplings for electron in magnetically confined semiconductor nanostructure,which is constructed on the GaAs/AlxGa1-xAs heterostructure.Schrödinger equation of an electron is numerically solved by matrix diagonalization and improved transfer-matrix method.Adopting H.G.Winful's theory,dwell time of electron is calculated and spin polarization ratio is given.Due to Zeeman effect and spin-orbit coupling,dwell time of electron is obviously associated with the spins,which is used to separate electron-spins in time dimension and to realize spin polarization of electrons in semiconductors.Because the semiconductor GaAs has a small effective g-factor,electron-spin polarization originates mainly from spin-orbit coupling including Rashba and Dresselhaus types,which is circa 4 times larger than that induced by Zeeman effect.Dwell time of electron and its spin polarization can be efficaciously modified by interfacial confining electric-field or strain engineering,as the effective potential of electron is related to spin-orbit coupling's strength.These interesting findings not only have some references for spin injection into semiconductors,but also provide a controllable temporal electron-spin splitter for semiconductor spintronics device applications.-
Keywords:
- Semiconductor spintronics /
- Magnetically confined semiconductor nanostructure /
- Spin-orbit coupling /
- Dwell time
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[1] Wolf S A, Awschalom D D, Buhrman R A, Daughton J M, von Molnár S, Roukes M L, Chtchelkanova A Y, Treger D M 2001 Science 294 1488
[2] Žutíc I, Fabiam J, Sarma S Das 2004 Rev. Mod. Phys. 76 323
[3] Gong C, Zhang X 2019 Science 363 705
[4] Soumyanrayanan A, Reyren N, Fert A, Panagopoulos C 2016 Nature 539 509
[5] Jiang L X, Li Q C, Zhang X, Li J F, Zhang J, Chen Z X, Zeng M, Wu H 2024 Acta Phys. Sin. 73 017505(in Chinese)[蒋龙兴,李庆超,张旭,李京峰,张静,陈祖信,曾敏,吴昊2024物理学报73 017505(中文)
[6] Gurram M, Omar S, Wees BJV 2017 Nat. Commun. 8 248
[7] Zhu W K, Lin H L, Yan F G et al. 2021 Adv. Material. 33 2104658
[8] Zhu W K, Xie S H, Lin H L et al. 2022 Chinese Phys. Lett. 39 128501
[9] Zhu W K, Zhu J M, Zhou T et al. 2023 Nat. Commun. 14 5371
[10] Kitchen D, Richardella A, Tang J M, Flatté M E, Yazdani A 2006 Nature 442 436
[11] He Y P, Chen M X, Pan J F, Li D, Lin G J, Huang X H 2023 Acta Phys. Sin. 72 028503(in Chinese)[贺亚萍,陈明霞,潘杰锋,李冬,林港钧,黄新红2023物理学报72 028503(中文)
[12] Li C L, Zheng J, Wang X M, Xu Y 2023 Acta Phys. Sin. 72 227201(in Chinese)[李春雷,郑军,王小明,徐燕2023物理学报72 227201(中文)
[13] Liu XH, Zhang GL, Kong YH, Li AH, Fu X 2014 Appl. Surf. Sci. 313 545
[14] Wang L, Guo Y 2006 Phys. Rev. B 73 205311
[15] Das S, Ghosh S, Kumar R, Bag A, Biswas D 2017 IEEE Trans. Electron Devices 64 4650
[16] Kong Y H, Liu X H, Li A H, Gong Y J 2019 Vacuum 159 410
[17] Nogaret A. 2010 J. Phys. Condens. Matter 22 253201
[18] Hauge E H, Støvneng J A 1989 Rev. Mod. Phys. 61 917
[19] Wang R Q, Gong J, Wu J Y, Chen J 2013 Acta Phys. Sin. 62 087303(in Chinese)[王瑞琴,宫箭,武建英,陈军2013物理学报62 087303(中文)
[20] Winful H G 2003 Phys. Rev. Lett. 91 260401
[21] Zhai F, Guo Y, Gu B L 2002 Eur. Phys. J. B 29 147
[22] Xu H Z, Liu P J, Zhang Y F 2003 Phys. Status Solidi B 240 169
[23] Chen S Y, Zhang G L, Cao X L, Peng F F 2021 J. Comput. Electron. 20 785
[24] Zhang G L, Lu M W, Chen S Y, Peng F F, Meng J S 2021 IEEE Trans. Magn. 57 1400305
[25] Guo Q M, Lu M W, Huang X H, Yang S Q, Qin Y J 2021 Vacuum 186 110059
[26] Xie S S, Lu M W, Huang X H, Wen L, Chen J L 2023 Phys. Lett. A 480 128976
[27] Guo Q M, Lu M W, Yang S Q, Qin Y J, Xie S S 2022 Braz. J. Phys. 52 74
[28] Lu M W, Chen S Y, Cao X L,Huang X H 2021 IEEE Trans. Electron Devices 68 860
[29] Capasso F, Mohammed K, Cho A Y, Hull R, Hutchinson A L 1985 Appl. Phys. Lett. 47 420
[30] Lu M W, Chen S Y, Cao X L, Huang X H 2020 Results Phys. 19 103375
[31] Chen S Y, Cao X L, Huang X H, Lu M W 2023 Eur. Phys. J. Plus 138 111
[32] Xie S S, Lu M W, Huang X H, Wen L, Chen J L 2023 Results Phys. 51 106605
[33] Guo Q M, Chen S Y, Cao X L, Yang S Q 2021 Semicond. Sci. Technol. 36 055013
[34] Guo Q M, Lu M W, Yang S Q, Qin Y J, Xie S S 2022 J. Nanoelectron. Optoe. 16 1554
[35] Chen S Y, Lu M W, Cao X L 2022 Chin Phys B 31 017201
[36] Lu M W, Chen S Y, Zhang G L, Huang X H 2018 IEEE Trans. Electron Devices 65 3045
[37] Rashba E I, Efros A L 2003 Phys. Rev. Lett. 91 126405
[38] Schliemann J, Loss D 2003 Phys. Rev. B 68 165311
[39] Bindel J R, Pezzotta M, Ulrich J, Liebmamm M, sheman E Y, Morgenstern M 2016 Nat. Phys. 12 920
[40] Intronati G A, Tamborenea P I, Weinmann D A, Jarabert R A 2012 Phys. Rev. Lett. 108 016601
[41] Xie S S, Lu M W, Chen S Y, Qin Y J, Wen L, Chen J L 2023 Commun. Theor. Phys. 75 015703
[42] Bergmann K von, Heinze S, Bode M, Vedmedenko E Y, Bihlmayer G, Blügel S, Wiesendanger R 2006 Phys. Rev. Lett. 96 167203
[43] Lu M W, Chen S Y, Zhang G L 2017 IEEE Trans. Electron Devices 64 1825
[44] You J Q, Zhang L D, Ghosh P K 1995 Phys. Rev. B 52 17243
[45] Lu M W, Chen S Y, Zhang G L, Huang X H 2018 J. Phys.-Condens. Matter 30 145302
[46] Lu K Y, He Z Y, Zu M M, Guo S Y 2022 IEEE Electron Device Lett. 43 1645
[47] Lu K Y, He Z Y, Zu M M, Guo S Y, Lu M W 2023 IEEE Electron Device Lett. 44 1424
[48] Rusetsky V S, Golyashov V A, Eremeev S V, Kusdov D A, Rusinov I P, Shamirzaev T S, Mironov A V, Demin A Yu, Tereshchenko O E 2022 Phys. Rev. Lett. 129 166802
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