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First-principles calculations of magnetic and optical properties of Ga1–xCrxSb (x = 0.25, 0.50, 0.75)

Wang Chuang Zhao Yong-Hong Liu Yong

First-principles calculations of magnetic and optical properties of Ga1–xCrxSb (x = 0.25, 0.50, 0.75)

Wang Chuang, Zhao Yong-Hong, Liu Yong
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  • As the demand for electronic devices increases continually, the spintronic materials have played an important role in materials science and electronics. Spintronic devices have excellent properties such as non-volatility, low power consumption, and high integration compared with conventional semiconductor devices. In this paper, we investigate the electronic structure, magnetic and optical properties of the semiconductor GaSb doped with 3d transition metal Cr, based on first-principles calculations. The compounds are constructed by replacing some Ga atoms with Cr in zinc-blende GaSb semiconductor, where the concentrations of the Ga atoms replaced are 0, 0.25, 0.50, and 0.75. We adopt the projected plane wave method and the electronic exchange correlation functional PBE in the generalized gradient approximation. Band gap is modified by Heyd-Scuseria-Ernzerhof (HSE06) functional. We study the equilibrium lattice constants of Cr-doped GaSb in zinc-blende structure at different concentrations. The energy of nonmagnetic, ferromagnetic and antiferromagnetic states at the equilibrium lattice constants are compared to identify the ground state. For Ga1–xCrxSb (x = 0.25, 0.50, 0.75), we find that the most stable state is ferromagnetic state. In the electronic structure of the ground state, the spin-up bands pass through the Fermi level while the spin-down bands each have a direct band gap. The Ga1–xCrxSb exhibit ferromagnetic half-metallic properties. The magnetic properties at different lattice constants under different concentrations are studied. Our analysis indicates that the Ga1–xCrxSb have integer Bohr magnetic moments of 3.0, 6.0, 9.0 μB for x = 0.25, 0.50 and 0.75, respectively. We find that when the lattice changes fom –5% to 20%, the total magnetic moment for each of Ga1–xCrxSb still remains the integer Bohr magnetic moment, and the magnetic moment of the Cr increases with the lattice constant increasing. We also find that the ferromagnetisms of Ga1–xCrxSb have Curie temperatures above room temperature, estimated by mean-field method. The p-d electron hybridization occurs in Cr-3d orbital and Sb-5p orbital, and the electron state density distribution of Cr-3d is transferred, that is, the electron orbital hybridization makes the total electron state density of crystal material redistributed, which is the main reason why Ga1–xCrxSb (x = 0.25, 0.50, 0.75) present ferromagnetic half-metallic properties. Additionally, the Ga1–xCrxSb have good absorption ability in the infrared region, compatible with zinc-blende semiconductors such as GaSb, which makes Ga1–xCrxSb have promising potential applications in both spintronic devices and infrared optoelectronic devices.
      Corresponding author: Liu Yong, yongliu@ysu.edu.cn
    [1]

    Prinz G A 1998 Science 282 1660

    [2]

    Ohno H, Munekata H, Penney T, von Molnar S, Chang L L 1992 Phys. Rev. Lett. 68 2664

    [3]

    Groot R A D, Mueller F M, Engen P G V, Buschow K H J 1983 Phys. Rev. Lett. 50 2024

    [4]

    Chen S, Ren Z 2013 Mater. Today 16 387

    [5]

    Watts S M, Wirth S, Von Molnár S, Barry A, Coey J M D 2000 Phys. Rev. B 61 9621

    [6]

    Xie W H, Liu B G 2004 J. Appl. Phys. 96 3559

    [7]

    Doumi B, Mokaddem A, Temimi L, Beldjoudi N, Elkeurti M, Dahmane F, Sayede A, Tadjer A, Ishak-Boushaki M 2015 Eur. Phys. J. B 88 93

    [8]

    Pickett W E, Moodera J S 2001 Phys. Today 54 39

    [9]

    Osborne Ian S 2001 Science 294 1483

    [10]

    Zutic I, Fabian J, Sarma S D 2004 Rev. Mod. Phys. 76 323

    [11]

    Katsnelson M I, Irkhin V Y, Chioncel L, Lichtenstein A I, de Groot R A 2008 Rev. Mod. Phys. 80 315

    [12]

    Chadov S, Graf T, Chadova K, Casper F, Fecher G H, Dai X F, Felser C 2011 Phys. Rev. Lett. 107 047202

    [13]

    Alijani V, Winterlik J, Fecher G H, Naghavi S S, Felser C 2011 Phys. Rev. B 83 184428

    [14]

    Liu H, Zhang J M 2017 Phys. Status Solidi B 254 1700098

    [15]

    Lin H F, Lau W M, Zhao J 2017 Sci. Rep. 7 45869

    [16]

    Coey J M D 2005 Solid State Sci. 7 660

    [17]

    Yang K, Wu R, Shen L, Feng Y P, Dai Y, Huang B 2010 Phys. Rev. B 81 125211

    [18]

    Katayama-Yoshida H, Sato K 2003 Physica B 327 337

    [19]

    Tu N T, Hai P N, Anh L D, Tanaka M 2016 Appl. Phys. Lett. 108 192401

    [20]

    Anh L D, Kaneko D, Hai P N, Tanaka M 2015 Appl. Phys. Lett. 107 232405

    [21]

    Ahmad I, Amin B 2013 Comput. Mater. Sci. 68 55

    [22]

    黄保瑞, 张富春, 王海洋 2016 电子元件与材料 35 34

    Huang B R, Zhang F C, Wang H Y 2016 Electronic Components and Materials 35 34

    [23]

    Shirai M 2001 Physica E 10 143

    [24]

    Hass M, Henvis B W 1962 J. Phys. Chem. Solids 23 1099

    [25]

    Ehrenreich H 1961 J. Appl. Phys. 32 2155

    [26]

    Liu Y, Liu B G 2007 J. Phys. D-Appl. Phys. 40 6791

    [27]

    Noor N A, Ali S, Shaukat A 2011 J. Phys. Chem. Solids 72 836

    [28]

    Rahman G, Cho S, Hong S C 2007 Phys. Status Solidi B 244 4435

    [29]

    Shinya H, Fukushima T, Masago A, Sato K, Katayama-Yoshida H 2018 J. Appl. Phys. 124 103902

    [30]

    Luo K W, Xu L, Wang L L, Li Q, Wang Z 2016 Comput. Mater. Sci. 117 300

    [31]

    Abe E, Sato K, Matsukura F, Zhao J H, Ohno Y, Ohno H 2004 J. Supercond. Nov. Magn. 17 349

    [32]

    Seña N, Dussan A, Mesa F, Castaño E, González-Hernández R 2016 J. Appl. Phys. 120 051704

    [33]

    Milnes A G, Polyakov A Y 1993 Solid-State Electron. 36 803

    [34]

    Zhang H I, Callaway J 1969 Phys. Rev. 181 1163

    [35]

    Ahmed R, Hashemifar S J, Rashid H, Akbarzadeh H 2009 Commun. Theor. Phys. 52 527

    [36]

    Schottky W F, Bever M B 1958 Acta Metall. 6 320

    [37]

    Bennett B R, Soref R A 1987 IEEE J. Quantum Electron. 23 2159

    [38]

    Aspnes D E, Studna A A 1983 Phys. Rev. B 27 985

    [39]

    Wei Y, Gin A, Razeghi M, Brown G J 2002 Appl. Phys. Lett. 81 3675

    [40]

    Rothmayr F, Pfenning A, Kistner C, Koeth J, Knebl G, Schade A, Höfling S 2018 Appl. Phys. Lett. 112 161107

    [41]

    Lin X, Pan F 2018 Mater. Res. Express 6 015901

    [42]

    Liu L H, Yu L H 2015 Intermetallics 57 139

    [43]

    Varshney D, Joshi G, Varshney M, Shriya S 2010 Physica B 405 1663

    [44]

    Amin B, Arif S, Ahmad I, Maqbool M, Ahmad R, Goumri-Said S, Prisbrey K 2011 J. Electron. Mater. 40 1428

    [45]

    Dresselhaus G 1955 Phys. Rev. 100 580

    [46]

    Cohen M L, Bergstresser T K 1966 Phys. Rev. 141 789

    [47]

    Zerouali A, Mokaddem A, Doumi B, Dahmane F, Elkeurti M, Sayede A, Tadjer A 2016 J. Comput. Electron. 15 1255

    [48]

    Liu X, Fan H Q 2018 Chin. Phys. B 27 86104

    [49]

    Peng G W, Gan X P, Li Z, Zhou K C 2018 Chin. Phys. B 27 86302

    [50]

    Kresse G, Hafner J 1993 Phys. Rev. B 48 13115

    [51]

    Kresse G, Furthmüller J 1996 Phys. Rev. B 54 11169

    [52]

    Kresse G 1999 Phys. Rev. B 59 1758

    [53]

    Perdew J P, Chevary J A, Vosko S H, Jackson K A, Pederson M R, Singh D J, Fiolhais C 1992 Phys. Rev. B 46 6671

    [54]

    Perdew J P, Burke K, Ernzerhof M 1996 Phys. Rev. Lett. 77 3865

    [55]

    Batista E R, Heyd J, Hennig R G, Uberuaga B P, Martin R L, Scuseria G E, Wilkins J W 2006 Phys. Rev. B 74 121102

    [56]

    Heyd J, Scuseria G E, Ernzerhof M 2003 J. Chem. Phys. 118 8207

    [57]

    Cang Y P, Lian S B, Yang H M, Chen D 2016 Chin. Phys. Lett. 33 66301

    [58]

    Zhu Z Y, Wang S Q, Fu Y M 2016 Chin. Phys. Lett. 33 26302

    [59]

    Wu J H, Liu C X 2016 Chin. Phys. Lett. 33 36202

    [60]

    原野, 田博博, 段纯刚 2018 物理学报 67 157511

    Yuan Y, Tian B B, Duan C G 2018 Acta Phys. Sin. 67 157511

    [61]

    Shirai M 2003 J. Appl. Phys. 93 6844

    [62]

    Cheng Y C, Zhu Z Y, Mi W B, Guo Z B, Schwingenschlögl U 2013 Phys. Rev. B 87 100401

    [63]

    Fukushima T, Sato K, Katayama-Yoshida H, Dederichs P H 2004 Jpn. J. Appl. Phys. 43 L1416

    [64]

    Şaşıoğlu E, Sandratskii L M, Bruno P 2004 Phys. Rev. B 70 024427

    [65]

    Liu B G 2003 Phys. Rev. B 67 172411

    [66]

    Kim Y S, Marsman M, Kresse G, Tran F, Blaha P 2010 Phys. Rev. B 82 205212

    [67]

    Guo S D, Liu B G 2011 EPL 93 47006

    [68]

    Zheng F, Zhou G, Liu Z, Wu J, Duan W, Gu B L, Zhang S B 2008 Phys. Rev. B 78 205415

    [69]

    De Paiva R, Nogueira R A, Alves J L A 2004 J. Appl. Phys. 96 6565

    [70]

    Chen Z Y, Xu B, Gao G Y 2013 J. Magn. Magn. Mater. 347 14

    [71]

    Arif S, Ahmad I, Amin B 2012 Int. J. Quantum Chem. 112 882

    [72]

    Nabi A, Akhtar Z, Iqbal T, Ali A, Javid M A 2017 J. Semicond. 38 073001

    [73]

    王逸飞, 李晓薇 2018 物理学报 67 116301

    Wang Y F, Li X W 2018 Acta Phys. Sin. 67 116301

  • 图 1  闪锌矿结构GaSb (a)结构图; (b)能带图

    Figure 1.  (a) Zinc-blende structure and (b) band structure of GaSb.

    图 2  晶体Ga1–xCrxSb (x = 0.25, 0.50, 0.75)结构优化的能量-体积关系图 (a) Ga0.75Cr0.25Sb; (b) Ga0.5Cr0.5Sb; (c) Ga0.25Cr0.75Sb; (d) Ga0.25Cr0.75Sb的铁磁态及两种反铁磁性磁序分布

    Figure 2.  The energy-volume curve of Ga1–xCrxSb (x = 0.25, 0.50, 0.75): (a) Ga0.75Cr0.25Sb; (b) Ga0.5Cr0.5Sb; (c) Ga0.25Cr0.75Sb; (d) the FM is ferromagnetic state and AFM stands for two types of antiferromagnetic state for Ga0.25Cr0.75Sb.

    图 3  Ga1–xCrxSb单胞总磁矩及Cr-d轨道和Sb-p轨道贡献磁矩随晶格变化图 同一颜色的表示是同一浓度材料, 线上的方块、三角、圆形分别表示总磁矩、Cr原子d轨道贡献磁矩和Sb原子p轨道贡献磁矩

    Figure 3.  The total magnetic moment per formula and the contribution of magnetic moment from Cr-d and Sb-p orbits as a function of the relative change of lattice constant of Ga1–xCrxSb. The same color represents the same concentration. The square, triangle and circle on the line represent the total magnetic moment, the contribution magnetic moment of the Cr atom d-orbit, and the magnetic moment of the Sb atom p-orbit, respectively.

    图 4  自旋能带结构图 (a) Ga0.75Cr0.25Sb; (b) Ga0.5Cr0.5Sb; (c) Ga0.75Cr0.25Sb; (d) CrSb

    Figure 4.  The spin-dependent band structure: (a) Ga0.75Cr0.25Sb; (b) Ga0.5Cr0.5Sb; (c) Ga0.25Cr0.75Sb; (d) CrSb.

    图 5  晶体电子态密度图 (a) GaSb; (b) Ga0.75Cr0.25Sb

    Figure 5.  Total electron density states of (a) GaSb; (b) Ga0.75Cr0.25Sb.

    图 6  Ga1–xCrxSb (x = 0, 0.25, 0.50, 0.75)的光学性质图谱对比 (a)折射系数; (b)反射率; (c)吸收系数

    Figure 6.  Comparison of optical properties of Ga1–xCrxSb (x = 0, 0.25, 0.50, 0.75): (a) The calculated optical refractive index; (b) the calculated optical reflectivity; (c) the calculated optical absorption coefficient.

    表 1  Ga1–xCrxSb (x = 0, 0.25, 0.50, 0.75, 1.00)总磁矩Mtot/NCr, Cr原子d轨道磁矩MCr, Sb原子p轨道磁矩MSb, 居里温度, 其中SM表示半导体, HMF表示半金属铁磁体

    Table 1.  Ga1–xCrxSb (x = 0, 0.25, 0.50, 0.75, 1.00) magnetic moment Mtot/NCr, Cr atom d-orbit magnetic moment MCr, Sb atom p-orbit magnetic moment MSb, Curie temperature, SM and HMF represent semiconductor and half-metal ferromagnetic, respectively.

    Mtot/NCr/μB MCr/μB MSb/μB 居里温度/K 基态性质 材料性质
    GaSb 0 NF SM
    Ga0.75Cr0.25Sb 3.00 3.266 –0.124 872 FM HMF
    Ga0.5Cr0.5Sb 3.00 3.113 –0.143 1104 FM HMF
    Ga0.25Cr0.75Sb 3.00 3.224 –0.176 1372 FM HMF
    CrSb 3.00 3.154 –0.152 1600[61] FM HMF
    DownLoad: CSV

    表 2  Ga1–xCrxSb (x = 0, 0.25, 0.50, 0.75, 1.00)系列晶体各项性质, a0表示平衡晶格常数, LCS表示Cr—Sb键长, LGS表示Ga—Sb键长, HMHSE表示用HSE方法得到的半金属能隙(eV), HMPBE表示用PBE方法得到的半金属能隙(eV), SMHSE表示用HSE方法得到的半导体能隙(eV), SMPBE表示用PBE方法得到的半导体能隙(eV)

    Table 2.  Crystals Properties of Ga1–xCrxSb (x = 0, 0.25, 0.50, 0.75, 1.00), the equilibrium lattice constant a0, Cr—Sb bond length LCS, Ga—Sb bond length LGS, the half-metal gap (eV) calculated by HSE HMHSE, denotes the half-metal gap (eV) calculated by PBE HMPBE, the semiconductor gap (eV) calculated by HSE SMHSE, and the semiconductor gap (eV) calculated by PBE SMPBE.

    a0 LCS LGS HMHSE HMPBE SMHSE SMPBE
    GaSb 6.095 2.638 0.526 0.083
    0.720[66] 0.110[66]
    Ga0.75Cr0.25Sb 6.210 2.652 2.702 0.137 0.121 1.275 0.637
    Ga0.5Cr0.5Sb 6.181 2.653 2.713 0.403 1.281 0.653
    Ga0.25Cr0.75Sb 6.159 2.654 2.725 0.613 1.305 0.664
    CrSb 6.128 2.654 0.657 0.750 2.327 1.52
    0.774[65] 1.646[65]
    0.751[67] 1.650[67]
    DownLoad: CSV
  • [1]

    Prinz G A 1998 Science 282 1660

    [2]

    Ohno H, Munekata H, Penney T, von Molnar S, Chang L L 1992 Phys. Rev. Lett. 68 2664

    [3]

    Groot R A D, Mueller F M, Engen P G V, Buschow K H J 1983 Phys. Rev. Lett. 50 2024

    [4]

    Chen S, Ren Z 2013 Mater. Today 16 387

    [5]

    Watts S M, Wirth S, Von Molnár S, Barry A, Coey J M D 2000 Phys. Rev. B 61 9621

    [6]

    Xie W H, Liu B G 2004 J. Appl. Phys. 96 3559

    [7]

    Doumi B, Mokaddem A, Temimi L, Beldjoudi N, Elkeurti M, Dahmane F, Sayede A, Tadjer A, Ishak-Boushaki M 2015 Eur. Phys. J. B 88 93

    [8]

    Pickett W E, Moodera J S 2001 Phys. Today 54 39

    [9]

    Osborne Ian S 2001 Science 294 1483

    [10]

    Zutic I, Fabian J, Sarma S D 2004 Rev. Mod. Phys. 76 323

    [11]

    Katsnelson M I, Irkhin V Y, Chioncel L, Lichtenstein A I, de Groot R A 2008 Rev. Mod. Phys. 80 315

    [12]

    Chadov S, Graf T, Chadova K, Casper F, Fecher G H, Dai X F, Felser C 2011 Phys. Rev. Lett. 107 047202

    [13]

    Alijani V, Winterlik J, Fecher G H, Naghavi S S, Felser C 2011 Phys. Rev. B 83 184428

    [14]

    Liu H, Zhang J M 2017 Phys. Status Solidi B 254 1700098

    [15]

    Lin H F, Lau W M, Zhao J 2017 Sci. Rep. 7 45869

    [16]

    Coey J M D 2005 Solid State Sci. 7 660

    [17]

    Yang K, Wu R, Shen L, Feng Y P, Dai Y, Huang B 2010 Phys. Rev. B 81 125211

    [18]

    Katayama-Yoshida H, Sato K 2003 Physica B 327 337

    [19]

    Tu N T, Hai P N, Anh L D, Tanaka M 2016 Appl. Phys. Lett. 108 192401

    [20]

    Anh L D, Kaneko D, Hai P N, Tanaka M 2015 Appl. Phys. Lett. 107 232405

    [21]

    Ahmad I, Amin B 2013 Comput. Mater. Sci. 68 55

    [22]

    黄保瑞, 张富春, 王海洋 2016 电子元件与材料 35 34

    Huang B R, Zhang F C, Wang H Y 2016 Electronic Components and Materials 35 34

    [23]

    Shirai M 2001 Physica E 10 143

    [24]

    Hass M, Henvis B W 1962 J. Phys. Chem. Solids 23 1099

    [25]

    Ehrenreich H 1961 J. Appl. Phys. 32 2155

    [26]

    Liu Y, Liu B G 2007 J. Phys. D-Appl. Phys. 40 6791

    [27]

    Noor N A, Ali S, Shaukat A 2011 J. Phys. Chem. Solids 72 836

    [28]

    Rahman G, Cho S, Hong S C 2007 Phys. Status Solidi B 244 4435

    [29]

    Shinya H, Fukushima T, Masago A, Sato K, Katayama-Yoshida H 2018 J. Appl. Phys. 124 103902

    [30]

    Luo K W, Xu L, Wang L L, Li Q, Wang Z 2016 Comput. Mater. Sci. 117 300

    [31]

    Abe E, Sato K, Matsukura F, Zhao J H, Ohno Y, Ohno H 2004 J. Supercond. Nov. Magn. 17 349

    [32]

    Seña N, Dussan A, Mesa F, Castaño E, González-Hernández R 2016 J. Appl. Phys. 120 051704

    [33]

    Milnes A G, Polyakov A Y 1993 Solid-State Electron. 36 803

    [34]

    Zhang H I, Callaway J 1969 Phys. Rev. 181 1163

    [35]

    Ahmed R, Hashemifar S J, Rashid H, Akbarzadeh H 2009 Commun. Theor. Phys. 52 527

    [36]

    Schottky W F, Bever M B 1958 Acta Metall. 6 320

    [37]

    Bennett B R, Soref R A 1987 IEEE J. Quantum Electron. 23 2159

    [38]

    Aspnes D E, Studna A A 1983 Phys. Rev. B 27 985

    [39]

    Wei Y, Gin A, Razeghi M, Brown G J 2002 Appl. Phys. Lett. 81 3675

    [40]

    Rothmayr F, Pfenning A, Kistner C, Koeth J, Knebl G, Schade A, Höfling S 2018 Appl. Phys. Lett. 112 161107

    [41]

    Lin X, Pan F 2018 Mater. Res. Express 6 015901

    [42]

    Liu L H, Yu L H 2015 Intermetallics 57 139

    [43]

    Varshney D, Joshi G, Varshney M, Shriya S 2010 Physica B 405 1663

    [44]

    Amin B, Arif S, Ahmad I, Maqbool M, Ahmad R, Goumri-Said S, Prisbrey K 2011 J. Electron. Mater. 40 1428

    [45]

    Dresselhaus G 1955 Phys. Rev. 100 580

    [46]

    Cohen M L, Bergstresser T K 1966 Phys. Rev. 141 789

    [47]

    Zerouali A, Mokaddem A, Doumi B, Dahmane F, Elkeurti M, Sayede A, Tadjer A 2016 J. Comput. Electron. 15 1255

    [48]

    Liu X, Fan H Q 2018 Chin. Phys. B 27 86104

    [49]

    Peng G W, Gan X P, Li Z, Zhou K C 2018 Chin. Phys. B 27 86302

    [50]

    Kresse G, Hafner J 1993 Phys. Rev. B 48 13115

    [51]

    Kresse G, Furthmüller J 1996 Phys. Rev. B 54 11169

    [52]

    Kresse G 1999 Phys. Rev. B 59 1758

    [53]

    Perdew J P, Chevary J A, Vosko S H, Jackson K A, Pederson M R, Singh D J, Fiolhais C 1992 Phys. Rev. B 46 6671

    [54]

    Perdew J P, Burke K, Ernzerhof M 1996 Phys. Rev. Lett. 77 3865

    [55]

    Batista E R, Heyd J, Hennig R G, Uberuaga B P, Martin R L, Scuseria G E, Wilkins J W 2006 Phys. Rev. B 74 121102

    [56]

    Heyd J, Scuseria G E, Ernzerhof M 2003 J. Chem. Phys. 118 8207

    [57]

    Cang Y P, Lian S B, Yang H M, Chen D 2016 Chin. Phys. Lett. 33 66301

    [58]

    Zhu Z Y, Wang S Q, Fu Y M 2016 Chin. Phys. Lett. 33 26302

    [59]

    Wu J H, Liu C X 2016 Chin. Phys. Lett. 33 36202

    [60]

    原野, 田博博, 段纯刚 2018 物理学报 67 157511

    Yuan Y, Tian B B, Duan C G 2018 Acta Phys. Sin. 67 157511

    [61]

    Shirai M 2003 J. Appl. Phys. 93 6844

    [62]

    Cheng Y C, Zhu Z Y, Mi W B, Guo Z B, Schwingenschlögl U 2013 Phys. Rev. B 87 100401

    [63]

    Fukushima T, Sato K, Katayama-Yoshida H, Dederichs P H 2004 Jpn. J. Appl. Phys. 43 L1416

    [64]

    Şaşıoğlu E, Sandratskii L M, Bruno P 2004 Phys. Rev. B 70 024427

    [65]

    Liu B G 2003 Phys. Rev. B 67 172411

    [66]

    Kim Y S, Marsman M, Kresse G, Tran F, Blaha P 2010 Phys. Rev. B 82 205212

    [67]

    Guo S D, Liu B G 2011 EPL 93 47006

    [68]

    Zheng F, Zhou G, Liu Z, Wu J, Duan W, Gu B L, Zhang S B 2008 Phys. Rev. B 78 205415

    [69]

    De Paiva R, Nogueira R A, Alves J L A 2004 J. Appl. Phys. 96 6565

    [70]

    Chen Z Y, Xu B, Gao G Y 2013 J. Magn. Magn. Mater. 347 14

    [71]

    Arif S, Ahmad I, Amin B 2012 Int. J. Quantum Chem. 112 882

    [72]

    Nabi A, Akhtar Z, Iqbal T, Ali A, Javid M A 2017 J. Semicond. 38 073001

    [73]

    王逸飞, 李晓薇 2018 物理学报 67 116301

    Wang Y F, Li X W 2018 Acta Phys. Sin. 67 116301

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  • Received Date:  29 December 2018
  • Accepted Date:  14 June 2019
  • Available Online:  26 November 2019
  • Published Online:  01 September 2019

First-principles calculations of magnetic and optical properties of Ga1–xCrxSb (x = 0.25, 0.50, 0.75)

    Corresponding author: Liu Yong, yongliu@ysu.edu.cn
  • 1. Key Laboratory for Microstructural Material Physics of Hebei Province, State Key Laboratory of Metastable Materials Science and Technology, School of Science, Yanshan University, Qinhuangdao 066004, China
  • 2. College of Physics and Electronic Engineering, Center for Computational Sciences, Sichuan Normal University, Chengdu 610068, China

Abstract: As the demand for electronic devices increases continually, the spintronic materials have played an important role in materials science and electronics. Spintronic devices have excellent properties such as non-volatility, low power consumption, and high integration compared with conventional semiconductor devices. In this paper, we investigate the electronic structure, magnetic and optical properties of the semiconductor GaSb doped with 3d transition metal Cr, based on first-principles calculations. The compounds are constructed by replacing some Ga atoms with Cr in zinc-blende GaSb semiconductor, where the concentrations of the Ga atoms replaced are 0, 0.25, 0.50, and 0.75. We adopt the projected plane wave method and the electronic exchange correlation functional PBE in the generalized gradient approximation. Band gap is modified by Heyd-Scuseria-Ernzerhof (HSE06) functional. We study the equilibrium lattice constants of Cr-doped GaSb in zinc-blende structure at different concentrations. The energy of nonmagnetic, ferromagnetic and antiferromagnetic states at the equilibrium lattice constants are compared to identify the ground state. For Ga1–xCrxSb (x = 0.25, 0.50, 0.75), we find that the most stable state is ferromagnetic state. In the electronic structure of the ground state, the spin-up bands pass through the Fermi level while the spin-down bands each have a direct band gap. The Ga1–xCrxSb exhibit ferromagnetic half-metallic properties. The magnetic properties at different lattice constants under different concentrations are studied. Our analysis indicates that the Ga1–xCrxSb have integer Bohr magnetic moments of 3.0, 6.0, 9.0 μB for x = 0.25, 0.50 and 0.75, respectively. We find that when the lattice changes fom –5% to 20%, the total magnetic moment for each of Ga1–xCrxSb still remains the integer Bohr magnetic moment, and the magnetic moment of the Cr increases with the lattice constant increasing. We also find that the ferromagnetisms of Ga1–xCrxSb have Curie temperatures above room temperature, estimated by mean-field method. The p-d electron hybridization occurs in Cr-3d orbital and Sb-5p orbital, and the electron state density distribution of Cr-3d is transferred, that is, the electron orbital hybridization makes the total electron state density of crystal material redistributed, which is the main reason why Ga1–xCrxSb (x = 0.25, 0.50, 0.75) present ferromagnetic half-metallic properties. Additionally, the Ga1–xCrxSb have good absorption ability in the infrared region, compatible with zinc-blende semiconductors such as GaSb, which makes Ga1–xCrxSb have promising potential applications in both spintronic devices and infrared optoelectronic devices.

    • 在过去几十年里, 自旋电子学发展迅速. 与传统的半导体器件相比, 自旋电子学器件具有存储非易失性、功耗低和集成度高等优势[1,2]. 1983年, Groot等[3]通过对三元赫斯勒(Heusler)合金NiMnSb和PtMnSb等合金的研究, 首次发现了一种新型的能带结构, 其中一个方向电子自旋能带呈现金属性, 而另一个方向的电子自旋能带呈现半导体性, 并把这种有着特殊能带结构的材料命名为“半金属铁磁体(half-metal ferromagnet HMF)”[4]. 这类铁磁半金属材料可以产生完全自旋极化的传导电子, 成为很好的自旋流注入源[5-7], 加上具有较高的居里温度、磁矩量子化和零磁化率等特殊的物理性质[8,9], 在制作自旋电子学器件如自旋二极管、自旋场效应管、自旋节流阀、自旋过滤器等方面具有重要应用前景. 它将不仅在新一代高性能微电子设备中发挥重要作用, 并且为极化输运理论以及自旋电子学的研究开辟崭新的领域[10-13].

      自旋电子学利用了电子的电荷与自旋作为信息的载体, 与传统半导体材料相比, 具有更优越的性能. 当前电子材料兼容的途径就是通过引入高浓度的磁性离子使非磁性半导体出现磁性, 甚至铁磁化. 随着自旋电子学材料的发展, 用磁性过渡金属元素离子注入二元半导体, 发现了同时具有磁性和半导体特性的新型磁性材料, 这在自旋电子学的研究中引起了人们极大的兴趣, 也为自旋电子学的发展起到了重要推动作用. 已有相关的研究工作发现, 将少量的磁性元素掺入II-VI族[14,15], IV族或III-V族等半导体中[16-18], 掺入的磁性原子替代半导体晶胞中的阳离子或阴离子, 或者通过缺陷技术在所研究的体系中形成缺陷, 研究发现了许多新型自旋电子学材料[19,20], Ahmad和Amin[21]发现Mn掺杂下Ga1–xMnxP和Ga1–xMnxAs是磁性半金属材料. 黄保瑞等[22]研究 了Cr掺杂纤锌矿GaN的磁性和光学性质, 发现Cr掺杂后材料在红外光区吸收增强, 具有优异的磁光性能. Shirai [23]采用3d过渡金属元素掺杂III-V族半导体GaAs, 研究发现多种半金属材料. 经过调研发现, III-V族化合物半导体材料在光电子器件、光电集成、超高速微电子器件和超高频微波器件及电路上等方面有着广阔应用[24,25]. 近年来通过利用过渡金属元素掺杂III-V族二元半导体发现了很多新型半金属材料[26-30]. 而近来研究人员对于III-V族半导体材料GaSb的关注逐渐提高, Abe等[31]利用分子束外延的实验方法研究了Cr掺杂GaSb的材料性质, 发现它们具有室温以上的铁磁性质. Seña等[32]利用密度泛函方法研究了Mn掺杂GaSb, 发现掺杂后的材料具有铁磁半金属性质. 所以我们选取过渡金属Cr替换半导体材料GaSb中的阳离子Ga, 利用第一性原理展开研究. GaSb是具有闪锌矿晶体结构的直接带隙半导体, 禁带宽度约为0.72 eV, 晶格常数为0.61 nm[33]. GaSb具有电子迁移率高、高频低阈值、光电转化率高等特点[34-36]. 同时这种材料的晶格常数与其他各种三元、四元的III-V族化合物半导体材料的晶格常数近似匹配, 可以大大减少由晶格失配导致的应力、缺陷等问题, 因此成为制备长波LED及光电探测器、光纤通信器件的重要衬底材料[37-40]. 对相关文献和已有同类型研究工作进展[41-44]进行了解后, 我们选用过渡金属Cr离子注入GaSb来尝试研究, 希望发现新的自旋电子学材料.

    2.   模型构建和计算方法
    • GaSb晶体具有闪锌矿结构 (Zinc-blende structure, ZB), 空间群是F-43m (空间群编号216)[45,46]. 在GaSb 2 × 2 × 2的超胞中, 每个Ga(Sb)原子处于四个最近邻Sb(Ga)原子的四面体中心, 其晶体结构如图1所示. 我们考虑在一个GaSb晶胞中由Cr替换Ga原子, 分别替换一个、两个、三个Ga原子, 即离子注入Cr比例分别为25%, 50%, 75%, 得到过渡金属元素Cr离子注入后的ZB Ga1–xCrxSb (x = 0.25, 0.50, 0.75)[47,48].

      Figure 1.  (a) Zinc-blende structure and (b) band structure of GaSb.

      本文主要利用第一性原理计算的方法[49]研究过渡金属Cr离子注入GaSb的电学、磁学和光学性质. 所有计算采用密度泛函理论的第一性原理计算软件包VASP(vienna ab initio simulation package)[50,51]. 在模拟计算中, 选择缀加投影平面波方法(projected augmented wave, PAW)[52]来描述电子与原子核之间的相互作用, 电子与电子之间的关联相互作用采用广义梯度近似(generalized gradient approximation, GGA)[53]中的PBE (Perdew Bueke Ernzerhof)[54]形式. 首先对各结构体系进行平面波截断能和布里渊区积分的Monkhorst-pack特殊K点选取进行优化. 经过测试, 平面波截断能取400 eV, K点网格大小选取7 × 7 × 7. 在晶体结构优化和原子弛豫过程中, 体系总能量收敛精度和单个原子上的力收敛精度分别为10–5 eV和10–4 eV/atom. 分别计算Ga1–xCrxSb (x = 0.25, 0.50, 0.75) 的无磁性、铁磁性和反铁磁性的总能量随晶格常数变化的关系. 因为PBE泛函计算会低估晶体带隙, 所以我们在计算电子能带时加入了杂化密度泛函Heyd-Scuseria-Ernzerhof (HSE06)[55,56]对电子能带计算进行修正, 使能带计算结果更加合理.

    3.   结果与分析
    • 计算了在不同浓度Cr离子注入下ZB Ga1–xCrxSb (x = 0.25, 0.50, 0.75)材料的电子基态性质[57]. 对于离子注入体系的铁磁态 (ferromagnetic, FM)、反铁磁态 (antiferro- magnetic, AFM)的计算, 主要是通过使偶数的Cr原子自旋呈现平行、反平行、交叉反平行来实现的, 我们在替换原子后的闪锌矿结构晶胞基础上扩为$ \sqrt {\rm{2}} \times \sqrt {\rm{2}} \times {\rm{1}}$的超胞, 并考虑结构对称性后分析磁序排列, 图2(d)为替换了75%的Ga后的铁磁态及两种反铁磁态. 蓝色和红色箭头分别表示Cr原子的上、下自旋方向. 图2(a)图2(c)展示了不同浓度Cr离子注入下的Ga1–xCrxSb三种磁性态对应的能量体积曲线 (E -V)图. 从图中可以看出, 铁磁态的能量随体积变化的曲线都低于反铁磁和非磁的曲线[58,59]. 因而, Ga1–xCrxSb处于平衡晶格常数时, 体系在铁磁态的总能量最低, 结构最稳定.

      Figure 2.  The energy-volume curve of Ga1–xCrxSb (x = 0.25, 0.50, 0.75): (a) Ga0.75Cr0.25Sb; (b) Ga0.5Cr0.5Sb; (c) Ga0.25Cr0.75Sb; (d) the FM is ferromagnetic state and AFM stands for two types of antiferromagnetic state for Ga0.25Cr0.75Sb.

      在Ga1–xCrxSb (x = 0.25, 0.50, 0.75)计算中发现, 当处于平衡晶格常数时, 它们的总磁矩为玻尔磁子μB的整数倍, Ga1–xCrxSb (x = 0.25, 0.50, 0.75)的整数总磁矩分别为3.0μB, 6.0μB, 9.0μB, 这一特性符合铁磁半金属的性质. 如图3所示为这三种铁磁半金属材料的磁矩随晶格常数变化在 ± 20%的关系, 我们发现总磁矩主要由Cr原子上d轨道贡献, 额外的贡献来自于位于Cr其他轨道和邻近的Sb原子的p轨道, 且Cr和Sb贡献的磁矩方向相反. 在 –5%—20%的晶格变化范围内, Ga1–xCrxSb总磁矩仍然保持μB整数倍不变, 而Cr-d轨道的贡献磁矩随着晶格常数的增加而增大, 并在达到平衡晶格常数后, 增大趋势减缓[60].

      Figure 3.  The total magnetic moment per formula and the contribution of magnetic moment from Cr-d and Sb-p orbits as a function of the relative change of lattice constant of Ga1–xCrxSb. The same color represents the same concentration. The square, triangle and circle on the line represent the total magnetic moment, the contribution magnetic moment of the Cr atom d-orbit, and the magnetic moment of the Sb atom p-orbit, respectively.

      GaSb中的Ga被Cr取代时, 首先Ga空位在价带中产生三个空穴, 留下Sb悬挂键. 当Cr占据Ga位点时, 它会提供三个电子以实现Cr-Sb键合. 然后Cr留下3个未配对的d电子, 产生3μB的磁矩. Cr和近邻的Sb之间的磁耦合总是反铁磁性的, 如表1所示. 可能是由于局部Cr-d轨道与Sb-p轨道之间的p-d交换相互作用, 从而实现了Cr离子注入后GaSb由无磁材料到磁性材料的转变. 这些结果表明, GaSb半导体可以作为实现自旋电子器件的母体材料.

      Mtot/NCr/μB MCr/μB MSb/μB 居里温度/K 基态性质 材料性质
      GaSb 0 NF SM
      Ga0.75Cr0.25Sb 3.00 3.266 –0.124 872 FM HMF
      Ga0.5Cr0.5Sb 3.00 3.113 –0.143 1104 FM HMF
      Ga0.25Cr0.75Sb 3.00 3.224 –0.176 1372 FM HMF
      CrSb 3.00 3.154 –0.152 1600[61] FM HMF

      Table 1.  Ga1–xCrxSb (x = 0, 0.25, 0.50, 0.75, 1.00) magnetic moment Mtot/NCr, Cr atom d-orbit magnetic moment MCr, Sb atom p-orbit magnetic moment MSb, Curie temperature, SM and HMF represent semiconductor and half-metal ferromagnetic, respectively.

      磁性材料的铁磁转变温度一直是关乎材料实际应用的一个重要问题, 而CrSb是已被研究证明的铁磁半金属材料, 我们采用与文献一致的平均场方法估算了三种铁磁半金属的居里温度[62-64],

      式中C表示在晶胞中的Cr离子注入浓度, kB表示玻尔兹曼常数, $ \Delta {E_{{\rm{FM}} - {\rm{AFM}}}}$表示体系铁磁态和反铁磁态的能量差. 计算发现它们都具有超过室温的居里温度, 对比文献中CrSb具有约1600 K的居里温度, 这一特性符合半金属铁磁体材料的特点. Ga1–xCrxSb (x = 0, 0.25, 0.5, 0.75, 1)的磁学性质及居里温度见表1.

    • 然后计算了平衡结构下Ga1–xCrxSb (x = 0.25, 0.50, 0.75, 1.00)的电子结构. 如图4所示, Ga1–xCrxSb具有相似的能带结构, 我们发现它们自旋向上的能带穿过费米能级EF, 呈金属性; 而自旋向下的能带在费米能级处都有一个带隙, 呈现半导体性, 符合半金属能带结构的特点. 由图4可以看出, 离子注入后的Ga1–xCrxSb的半导体性质能带导带底和价带顶都位于布里渊区Γ对称点, 属于直接带隙. 因为ZB结构的GaSb和CrSb晶体材料早已被研究, 我们还是采用本研究的方法计算了未离子注入的ZB GaSb, 得出GaSb具有直接带隙半导体性质[46], 及完全将Ga原子替换为Cr的ZB CrSb的电子结构, 和CrSb呈铁磁半金属性[65], CrSb能带图如图4(d)所示, 我们的结果与文献中的材料电子结构等性质一致(Ga1–xCrxSb (x = 0, 0.25, 0.50, 0.75, 1.00) 计算的平衡晶格常数和基态性质及相关文献值见表2). 通过对比发现, 离子注入Cr后GaSb出现铁磁半金属性质, 由此推测该系列半金属性是由离子注入的Cr原子所引起的.

      Figure 4.  The spin-dependent band structure: (a) Ga0.75Cr0.25Sb; (b) Ga0.5Cr0.5Sb; (c) Ga0.25Cr0.75Sb; (d) CrSb.

      a0 LCS LGS HMHSE HMPBE SMHSE SMPBE
      GaSb 6.095 2.638 0.526 0.083
      0.720[66] 0.110[66]
      Ga0.75Cr0.25Sb 6.210 2.652 2.702 0.137 0.121 1.275 0.637
      Ga0.5Cr0.5Sb 6.181 2.653 2.713 0.403 1.281 0.653
      Ga0.25Cr0.75Sb 6.159 2.654 2.725 0.613 1.305 0.664
      CrSb 6.128 2.654 0.657 0.750 2.327 1.52
      0.774[65] 1.646[65]
      0.751[67] 1.650[67]

      Table 2.  Crystals Properties of Ga1–xCrxSb (x = 0, 0.25, 0.50, 0.75, 1.00), the equilibrium lattice constant a0, Cr—Sb bond length LCS, Ga—Sb bond length LGS, the half-metal gap (eV) calculated by HSE HMHSE, denotes the half-metal gap (eV) calculated by PBE HMPBE, the semiconductor gap (eV) calculated by HSE SMHSE, and the semiconductor gap (eV) calculated by PBE SMPBE.

      计算得出半导体GaSb处于平衡晶格常数时Ga—Sb的键长为2.638 Å, 对比该系列铁磁半导体材料中各原子之间的键长, 如表2中所列, 可以看出, 离子注入过渡金属Cr后, 由于电负性差异和各原子间电子轨道杂化, Ga1–xCrxSb中Cr的最外层轨道电子在键合中被消耗. 因为在元素周期表中Cr的离子半径(0.615 Å)和电负性(1.66)小于Ga的离子半径(0.620 Å)和电负性(1.88). 所以Cr—Sb的离子键键强大于Ga—Sb的离子键强, 而长度小于后者. 当GaSb中Cr的离子注入浓度增加时, 晶胞体积变小, 同时由于Sb离子的位置更加偏向Cr离子, 所以相应的Ga—Sb键长变长了, 而Cr—Sb键长随浓度变化不大. 由表2可以看出, HMF Ga1–xCrxSb (x = 0.25, 0.50, 0.75, 1.00)的半导体带隙和半金属能隙都随浓度增大而增大. 半金属材料的半金属能隙(half- metal gap HM gap)是在存在带隙的自旋子能带中, 费米能距离价带顶或导带底这二者中间最小值[68].

      为了进一步研究该系列HMF材料出现半金属性质的原理, 因为Ga1–xCrxSb (x = 0.25, 0.50, 0.75)电子态密度比较相似, 所以选取Ga0.75Cr0.25Sb总态密度(total density of states, TDOS)和各原子分波态密度 (partial density of states, PDOS)为例进行分析, 为了更清晰地比较分析, 图5(a)图5(b)分别为GaSb和Ga0.75Cr0.25Sb的电子态. 从图5(a)可以看出GaSb电子态无自旋极化, 所以GaSb没有磁性. 而Ga0.75Cr0.25Sb在费米面附近上自旋的态密度呈金属性, 而下自旋态有一明显带隙呈现半导体性, 所以Ga0.75Cr0.25Sb表现出磁性. 由于在Ga0.75Cr0.25Sb的费米能级处只存在一种自旋取向的电子, 由自旋极化率的定义

      Figure 5.  Total electron density states of (a) GaSb; (b) Ga0.75Cr0.25Sb.

      其中$ {N_ \uparrow }(E)$$ {N_ \downarrow }(E)$分别为自旋向上和自旋向下的电子的态密度. 可以得出Ga0.75Cr0.25Sb传导电子的自旋极化率为100%, 这也是半金属材料的一大特点.

      因为大多数材料的电磁性质、光学性质等都是来自原子之间p-d, d-d和s-p-d电子轨道杂化, 我们认为这与各原子电子组态以及各原子间电子轨道杂化有关[69-72]. 由于Cr的价电子组态分别为3d54s1, Ga的价电子组态为4s24p1, 最外层4p轨道只有1个电子, 而Sb的价电子组态为5s25p3, 它的5p态有3个电子, 是半填满态(p态的满壳层为6电子). 并且对比晶体中各个原子间的键长及态密度图, 我们认为在费米能级附近发生了强烈的杂化作用. 如表2中所示, 过渡金属原子Cr-Sb原子间距要小于Cr-Ga间距离, 也就表明电子杂化主要发生在过渡金属原子Cr与Sb原子之间.

      从各原子分波态密度可以看出, Ga0.75Cr0.25Sb总电子态密度主要由Cr-d轨道电子贡献, 而Ga-p, Sb-p等其他电子轨道贡献较少. 从图5(b)中可以看出, TDOS和Cr-d的PDOS在–3—–0.5 eV的上自旋态和0.5—3 eV的下自旋态有相似的态密度分布. 并且Sb-p和Cr-d对应的PDOS在–3— –0.5 eV能量区段中具有类似的DOS形状. 这一现象揭示了Cr原子与其4个相邻的Sb原子之间的轨道杂化, 由于Cr原子取代相同位置处的Ga原子, 所以Cr将磁化转移到相邻的Sb原子上. 所以导带底部主要由Cr-d电子态占据, 价带部分是由Sb-p, Ga-p, Cr-d的电子占据, 因为Cr-d轨道和Sb-p轨道之间有较大的电子轨道杂化, Cr-d相互杂化作用随浓度增大也增加. 下自旋态中Sb的p态被Cr的d态推向较低的能量, 因此, 价带变为与Cr磁矩反平行的自旋极化. 此外, 由于下自旋态的费米能级没有电子态, 得到Ga1–xCrxSb是一个具有整数磁矩的半金属铁磁体. 这两种效应都增大了Cr-d电子的跃迁, 使得Cr-d带宽变大, 自旋向下带隙随着Cr浓度的增加呈增大趋势. Cr的3d轨道和Sb的5p轨道发生p-d电子杂化, Cr的3d电子态密度分布发生转移, 即电子轨道杂化使得晶体材料总的电子态密度重新分布, 这是Ga1–xCrxSb (x = 0.25, 0.50, 0.75)表现出铁磁半金属性的主要原因.

    • 固体的光学性质可以用介电函数$ \varepsilon (\omega )$来描述[51,54], 而介电函数$ \varepsilon (\omega )$是由实部和虚部两部分组成, 定义为

      由于Ga1–xCrxSb (x = 0.25, 0.50, 0.75)属于立方晶系, 可知其光学性质是各向同性的. 本文计算了Ga1–xCrxSb的介电常数$ {\varepsilon _{{xx}}}(\omega )$并对光学性质进行分析[73]. 图6展示了各项光学性质与入射光能量的关系, 列出部分晶体材料的折射系数、反射率、吸收系数的对比图. 可以利用介电函数的实部$ {\varepsilon _{1}}(\omega )$和虚部$ {\varepsilon _{2}}(\omega )$来得到固体的吸收系数$ \alpha (\omega )$、反射率$ R(\omega )$, 定义公式如下:

      Figure 6.  Comparison of optical properties of Ga1–xCrxSb (x = 0, 0.25, 0.50, 0.75): (a) The calculated optical refractive index; (b) the calculated optical reflectivity; (c) the calculated optical absorption coefficient.

      计算得出Ga0.75Cr0.25Sb静态折射系数n(0) = 7, 比GaSb静态折射系数n(0) = 4.6高, 静态反射率分别为R(0) = 0.56, 同样高于GaSb的静态反射率R(0) = 0.41. 由图6(a)图6(b)可看出, HMF Ga1–xCrxSb (x = 0.25, 0.50, 0.75)静态反射率和静态折射系数都要高于未离子注入GaSb的. 在折射图谱可以看出, 在0 —3.5 eV能量范围内, Ga1–xCrxSb的折射率整体呈逐渐减小的趋势, 在1.3—3.5 eV可见光的能量范围内, 这些材料对光的折射系数随着入射光能量的增加迅速减小, 且材料对红外线的折射能力要远远高于对紫外线的折射, 并且离子注入后的材料的静态折射系数和静态反射率都要高于GaSb的. 从不同浓度Cr离子注入的反射、折射图可以看出, 离子注入后的折射系数和反射率变化规律大致相近, 而离子注入浓度越高的反射折射性质变化越明显.

      图6(c)可知, 在0—5 eV能量范围内, GaSb及Ga1–xCrxSb四种物质的吸收系数整体呈逐渐增加的趋势. 在可见光区, 没有明显吸收峰, 且离子注入后材料的吸收系数与未离子注入差别不大, 而在红外光区, 即入射光子能量低于1.3 eV时, 由图可以看出, 离子注入后材料对红外光吸收明显优于GaSb的. 因此Ga1–xCrxSb (x = 0.25, 0.50, 0.75)具有对红外光较强的吸收能力这一特性, 很可能应用于相关的红外光电器件上.

    4.   结 论
    • 本文采用第一性原理计算方法研究了Cr离子注入半导体GaSb的电子结构、磁性质和光学性质. 计算得到Ga1–xCrxSb (x = 0.25, 0.50, 0.75) 的电子态密度、电子能带结构, 发现它们具有半金属铁磁性, 并且表现出电子完全自旋极化、整数磁矩、较宽的能隙和半金属隙以及超过室温的居里温度等特点, 这些都预示着半金属材料Ga1–xCrxSb在自旋电子学器件中将会有广泛的应用. 同时在对该系列材料的反射、折射等光学性质的研究中发现, Ga1–xCrxSb的光学性质很相似, 具有较大的静态反射和静态折射系数. 在可见光范围内吸收系数都很小, 对红外光吸收能力较强, 因此Ga1–xCrxSb也许能成为应用于红外光电器件的潜在材料.

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