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

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.