铁磁金属/绝缘体/铁磁半导体/普通金属(FM/I/FS/NM)磁性隧道结中的隧穿磁电阻效应  

Tunneling Magnetoresistance in Ferromagnetic Metal/Insulator/FerromagneticSemiconductor/Normal Metal(FM/I/FS/NM)Magnetic Tunneling Junctions

作　　者：李双伶 曾柏魁 谢征微[1] LI Shuangling;ZENG Bokui;XIE Zhengwei(College of Physics and Electronic Engineering,Sichuan Normal University,Chengdu 610066,Sichuan)

机构地区：[1]四川师范大学物理与电子工程学院,四川成都610066

出　　处：《四川师范大学学报（自然科学版）》2020年第2期230-235,共6页Journal of Sichuan Normal University（Natural Science）

基　　金：四川省教育厅自然科学基金重点项目(13ZA0149和16ZA0047)。

摘　　要：在已有的单自旋过滤磁性隧道结铁磁金属/绝缘体/铁磁绝缘体/普通金属(FM/I/FI/NM)研究的基础上,将其中的铁磁绝缘层(FI)换为铁磁半导体层(FS),研究了铁磁金属/绝缘体/铁磁半导体/普通金属(FM/I/FS/NM)磁性隧道结中的隧穿磁电阻(TMR)现象.结果表明:由于FS层中的自旋过滤效应和Rashba自旋轨道耦合的影响,FM/I/FS/NM结可以在FS层厚度较大的情况下获得非常大的TMR值,从而避免已有的FM/I/FI/NM单自旋过滤结(FI表示铁磁绝缘层)中TMR随FI层厚度增加而下降所导致FI层不能做的太厚带来的制备上的困难.同时,计算结果还显示,FM/I/FS/NM结的TMR随铁磁半导体层FS的厚度,FS层中的Rashba自旋轨道耦合强度和分子场的变化呈振荡变化,随绝缘层I厚度的增加呈饱和趋势.On the basis of existing researches of ferromagnetic metal/insulator/ferromagneticinsulator/normal metal(FM/I/FI/NM)single spin-filter magnetic tunneling junctions,the FI layer in FM/I/FI/NM single spin-filter magnetic tunneling junction is replaced with FS layer(FS represents the ferromagnetic semiconductors)and the effects of tunneling magnetic resistantces(TMRs)in ferromagnetic metal/insulator/ferromagnetic semiconductor/normal metal(FM/I/FS/NM)magnetic tunneling junction are studied in this paper.The results show that,as the influences of the spin filter and the Rashba spin orbit coupling effects in the FS layer,a large TMR can be obtained for large FS layer thickness and the manufacturing difficulties brought by the too small thickness of FI layers in the usual FM/I/FI/NM(FI represents the ferromagnetic insulator layer)single spin filter junction can be avoided.The results also show that,for the FM/I/FS/NM junctions,the TMR would oscillate with the FS layer thickness,the Rashba spin orbit coupling strength,the molecular field and would tend to saturation with the increasing of I layer thickness.

关 键 词：磁性隧道结 铁磁半导体 隧穿磁电阻 RASHBA自旋轨道耦合 

分 类 号：O441[理学—电磁学]