界面自旋翻转对有限尺寸的铁磁体/非磁性半导体/铁磁体体系自旋注入的影响(英文)  

Effect of Interface Spin-Flip Scattering on Spin Injection in a Finite Ferromagnetic/Nonmagnetic-semiconductor/Ferromagnetic Junction

作　　者：米仪琳[1,2] 张铭[1] 严辉[1] 

机构地区：[1]北京工业大学材料科学学院,北京100122 [2]北方工业大学理学院,北京100144

出　　处：《功能材料与器件学报》2009年第4期327-331,共5页Journal of Functional Materials and Devices

基　　金：中国国家自然科学基金(No60576012);北京市教育委员会科技发展计划面上项目(KM200510009008);北方工业大学校科研基金资助项目(磁隧道结中自旋相关的电子隧穿行为研究)

摘　　要：本文考虑了界面自旋翻转效应后对有限尺寸的铁磁体/非磁性半导体/铁磁体异质结中的自旋注入问题进行了系统的理论探讨。由于自旋在两种介质界面上发生的翻转散射,自旋极化流的每一个分量在界面上都不可能连续。计算结果表明,当自旋注入效率从0增加到100%的过程中,铁磁体/非磁性半导体/铁磁体异质结的隧穿磁阻增大了两个数量级。这一事实证明界面的自旋翻转效应直接影响着铁磁体/非磁性半导体/铁磁体异质结的隧穿磁阻。Considering the effect of the interface spin - flip scattering, the spin - injection across ferromagnet/nonmagnetic- semiconductor/ferromagnet heterostuctures with finite size was explored theoretically. Due to the fact that interfacial spin - flip scattering leads to spin - memory losses at the interfaces, the spin - up component of spin - polarized current could not be continuous across the interface. It is found that when the spin injection efficiency varies from zero to unity, the tunneling magnetoresistance of the ferromagnet/nonmagnetic -semiconductor/ferromagnet junction presents two orders of changes in magnitude, which reflects the fact that the spin -flip scattering at the interface directly affects the tunneling magnetoresistance of ferromagnet/nonmagnetic -semiconductor/ferromagnet.

关 键 词：自旋注入效率 有限尺寸 自旋翻转散射 

分 类 号：O469[理学—凝聚态物理]