Magnetic coupling in ferromagnetic semiconductor GaMnAs/AlGaMnAs bilayer devices  

作　　者：CAO YuFei LI YanYong LI YuanYuan WEI GuanNan JI Yang WANG KaiYou 

机构地区：[1]The State Key Laboratory of Superlattices and Microstructures,Institute of Semiconductors, Chinese Academy of Sciences

出　　处：《Science China(Physics,Mechanics & Astronomy)》2014年第8期1471-1475,共5页中国科学：物理学、力学、天文学（英文版）

基　　金：supported by the National Basic Research Program of China (Grant Nos. 2011CB922200 and 2009CB929301);the National Natural Science Foundation of China (Grant Nos. 11174272 and 61225021); EPSRC-NSFC joint (Grant No. 10911130232/A0402);WANG KaiYou also acknowledges the support of Chinese Academy of Sciences 100 Talent Program

摘　　要：We carefully investigated the ferromagnetic coupling in the as-grown and annealed ferromagnetic semiconductor GaMnAs/A1GaMnAs bilayer devices. We observed that the magnetic interaction between the two layers strongly affects the magnetoresistance of the GaMnAs layer with applying the out of plane magnetic field. After low temperature annealing, the magnetic easy axis of the A1GaMnAs layer switches from out of plane into in-plane and the interlayer coupling efficiency is reduced from up to 0.6 to less than 0.4. However, the magnetic coupling penetration depth for the annealed device is twice that of the as-grown bilayer device.We carefully investigated the ferromagnetic coupling in the as-grown and annealed ferromagnetic semiconductor GaMnAs/AlGaMnAs bilayer devices.We observed that the magnetic interaction between the two layers strongly affects the magnetoresistance of the GaMnAs layer with applying the out of plane magnetic field.After low temperature annealing,the magnetic easy axis of the AlGaMnAs layer switches from out of plane into in-plane and the interlayer coupling efficiency is reduced from up to 0.6 to less than 0.4.However,the magnetic coupling penetration depth for the annealed device is twice that of the as-grown bilayer device.

关 键 词：magnetic coupling MAGNETORESISTANCE bilayer structure ANNEALING anisotropic field 

分 类 号：O482.5[理学—固体物理]