Strong anti-strain capacity of CoFeB/MgO interface on electronic structure and state coupling

作     者：郭飞 吴雅苹 吴志明 陈婷 李恒 张纯淼 付明明 卢奕宏 康俊勇 

作者机构：Collaborative Innovation Center for Optoelectronic Semiconductors and Efficient DevicesFujian Provincial Key Laboratory of Semiconductors and ApplicationsDepartment of Physics Xiamen University 

出 版 物：《Chinese Physics B》 (中国物理B（英文版）)

年 卷 期：2018年第27卷第1期

页      面：552-558页

核心收录：

学科分类：07[理学] 0702[理学-物理学] 

基　　金：Project supported by the National Key Research and Development Program of China(Grant No.2016YFB0400801) the National Natural Science Foundation of China(Grant Nos.61774128,61674124,11604275,11304257,and 61227009) the Natural Science Foundation of Fujian Province of China(Grant Nos.2017J01012,2014J01026,2016J01037,and 2015J01028) the Fundamental Research Funds for the Central Universities,China(Grant Nos.20720150027,20720160044,20720160122,20720170085,20720170012,and 20720150033) 

主　　题：ferromagnet material/MgO interface biaxial strain state coupling first-principles calculation 

摘      要：Electronic structure and spin-related state coupling at ferromagnetic material （FM）/MgO （FM = Fe, CoFe, CoFeB） interfaces under biaxial strain are evaluated using the first-principles calculations. The CoFeB/MgO interface, which is su- perior to the Fe/MgO and CoFe/MgO interfaces, can markedly maintain stable and effective coupling channels for majority- spin A1 state under large biaxial strain. Bonding interactions between Fe, Co, and B atoms and the electron transfer between Bloch states are responsible for the redistribution of the majority-spin A1 state, directly influencing the coupling effect for the strained interfaces. Layer-projected wave function of the majority-spin Al state suggests slower decay rate and more stable transport property in the CoFeB/MgO interface, which is expected to maintain a higher tunneling magnetoresistance （TMR） value under large biaxial strain. This work reveals the internal mechanism for the state coupling al strained FM/MgO interfaces. This study may provide some references to the design and manufacturing of magnetic tunnel .junctions with high tunneling magnetoresistance effect.