The melilite-type compound (Sr_(1-x),A_x)_2MnGe_2S_6O(A=K,La) being a room temperature ferromagnetic semiconductor  

作　　者：Huan-Cheng Yang Ben-Chao Gong Kai Liu Zhong-Yi Lu 

机构地区：[1]Department of Physics and Beijing Key Laboratory of Opto-electronic Functional Materials & Micro-nano Devices, Renmin University of China, Beijing 100872, China

出　　处：《Science Bulletin》2018年第14期887-891,共5页科学通报（英文版）

基　　金：supported by the National Key Research and Development Program of China(2017YFA0302903);the National Natural Science Foundation of China(11774422 and 11774424)

摘　　要：The seeking of room temperature ferromagnetic semiconductors, which take advantages of both the charge and spin degrees of freedom of electrons to realize a variety of functionalities in devices integrated with electronic, optical, and magnetic storage properties, has been a long-term goal of scientists and engi- neers. Here, by using the spin-polarized density functional theory calculations, we predict a new series of high temperature ferromagnetic semiconductors based on the melilite-type oxysulfide Sr2MnGe2S60 through hole （K） and electron （La） doping. Due to the lack of strong antiferromagnetic superexchange between Mn ions, the weak antiferromagnetic order in the parent compound Sr2MnGe2S60 can be sup- pressed easily by charge doping with either p-type magnetic order. At a doping concentration of or n-type carriers, giving rise to the expected ferro- 25%, both the hole-doped and electron-doped compounds can achieve a Curie temperature （To） above 300 K. The underlying mechanism is analyzed. Our study provides an effective approach for exploring new types of high temperature ferromagnetic semiconductors.The seeking of room temperature ferromagnetic semiconductors, which take advantages of both the charge and spin degrees of freedom of electrons to realize a variety of functionalities in devices integrated with electronic, optical, and magnetic storage properties, has been a long-term goal of scientists and engineers. Here, by using the spin-polarized density functional theory calculations, we predict a new series of high temperature ferromagnetic semiconductors based on the melilite-type oxysulfide Sr_2MnGe_2S_6O through hole(K) and electron(La) doping. Due to the lack of strong antiferromagnetic superexchange between Mn ions, the weak antiferromagnetic order in the parent compound Sr_2MnGe_2S_6O can be suppressed easily by charge doping with either p-type or n-type carriers, giving rise to the expected ferromagnetic order. At a doping concentration of 25%, both the hole-doped and electron-doped compounds can achieve a Curie temperature(T_c) above 300 K. The underlying mechanism is analyzed.Our study provides an effective approach for exploring new types of high temperature ferromagnetic semiconductors.

关 键 词：Ferromagnetic semiconductor MELILITE Density functional theory calculations Hole doping Electron doping 

分 类 号：TM271[一般工业技术—材料科学与工程]