First-principles design of quantum superstructures for development of spin-electronics

用于自旋电子学发展的量子超结构的第一性原理设计

• 批准号: 12650312
• 负责人: SHIRAI Masafumi
• 金额: $ 2.24万
• 依托单位: Tohoku University (2002)Osaka University (2000-2001)
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2000
• 资助国家: 日本
• 起止时间: 2000 至 2002
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-12650312/
• 关键词: spin-electronics; first-principles method; materials design; half-metal; spin-polarized magnet; zinc-blende Cr compounds; antisite defect; quantum superstructure; スピントロニクス; 閃亜鉛鉱型ヒ化クロム; アンチサイト; ハーフメタリック; 閃亜鉛鉱型CrAs; 閃亜鉛鉱型CrSb; スピン・エレクトロニクス; ハ

Injection of spin-polarized carriers into semiconductors is a basic technology for manifestation of spin-electronic devices which exploit both electronic charge and spin degrees of freedom. In order to improve the efficiency of spin-injection into semiconductors, completely spin-polarized (half-metallic) ferromagnets and their quantum superstructures with semiconductors, which are expected to be promising candidates for the source of spin-injection, have been designed theoretically by using first-principles electronic structure calculations. The results obtained by this project are as follows:(1) New half-metallic ferromagnets, zinc-blende CrAs, CrSb, and CrP, are designed theoretically.(2) The spin-polarization in these materials in almost unaffected by the spin-orbit interaction.(3) Antisite defects, Cr impurities at As-sites, reduce the spin-polarization in zinc-blende CrAs.(4) Zinc-blende CrAs/GaAs (001) multilayer structures maintain the half-metallic behavior.(5) An inhomogeneous doping method in suggested to realize Si-based ferromagnetic semiconductors.

在半导体中注入自旋极化载流子是实现电子自旋器件的基本技术，该器件既利用电子电荷，又利用自旋自由度。为了提高自旋注入半导体的效率，利用第一性原理电子结构计算理论设计了完全自旋极化（半金属）铁磁体及其具有半导体的量子超结构，这些超结构有望成为自旋注入源的候选者。结果表明：(1)从理论上设计了新型半金属铁磁体，即锌-闪锌矿CrAs、CrSb和CrP。(2)这些材料的自旋极化几乎不受自旋轨道相互作用的影响。(3) as位上的反位缺陷，即Cr杂质，降低了混合锌CrAs的自旋极化。(4)锌-闪锌矿CrAs/GaAs（001）多层结构保持了半金属性质。(5)提出了一种非均匀掺杂的方法来实现硅基铁磁半导体。

项目成果

M.Mizuguchi, et al.: "Epitaxial growth of zinc-blende CrAs/GaAs multilayer"Journal of Applied Physics. 91・10. 7917-7919 (2002)

M.Mizuguchi等人：“闪锌矿CrAs/GaAs多层的外延生长”应用物理学杂志91・10（2002）。

Kenji Narita: "Electronic and magnetoresistive properties of MnAs(0001)/GaAs(111) heterostructures"Physica E. 10・. 433-436 (2001)

Kenji Narita：“MnAs(0001)/GaAs(111)异质结构的电子和磁阻特性”Physica E. 10・433-436 (2001)

M.Shirai: "Materials design of Cr-based half-metallic ferromagnets"Journal of Superconductivity : Incorporating Novel Magnetism. (発表予定). (2003)

M.Shirai：“Cr基半金属铁磁体的材料设计”超导杂志：结合新型磁学（即将出版）。

H. Akinaga et al.: "A new half-metallic ferromagnet - zinc-blende CrAs"Solid State Physics. 36-9. 587-592 (2001)

H. Akinaga 等人：“一种新型半金属铁磁体——闪锌矿 CrAs”固体物理。

T. Manago et al.: "Materials design and synthesis of half-metallic CrAs"Journal of Magnetics Society of Japan. 26-4. 441-444 (2002)

T. Manago等人：“半金属CrAs的材料设计与合成”日本磁学学会杂志。