First-Principles Studies for Magnetism in Cu-Doped GaN  

作　　者：YANG Qin SUN Fang TANG Zheng 

机构地区：[1]Department of Electronic and Engineering, East China Normal University, Shanghai 200241, China

出　　处：《Wuhan University Journal of Natural Sciences》2011年第3期245-248,共4页武汉大学学报（自然科学英文版）

基　　金：Supported by the National Basic Research Program of China (973 Program) (2007CB924902);the National Natural Science Foundation of China (10775053, 61076089);the "Shu Guang" Project of Shanghai Education Development Foundation (09SG24)

摘　　要：Hole carrier mediated magnetization in Cu-doped GaN is investigated by using the first-principles calculations. By studying the sp-d interaction and the direct exchange interaction among the dopants, we obtain an equation to determine the spontaneous magnetization as a function of the Cu dopant concentration and the hole carrier density. It is demonstrated that nonmagnetic Cu doped GaN can be of room-temperature ferromagnetism. The system＇s Curie temperature Tc can reach about 345 K with Cu concentration of 1.0% and hole carrier density of 5.0×10^19 cm-3. The results are in good agreement with experimental observations and indicate that ferromagnetism in this systems is tunable by controlling the Cu concentration and the hole carrier density.Hole carrier mediated magnetization in Cu-doped GaN is investigated by using the first-principles calculations. By studying the sp-d interaction and the direct exchange interaction among the dopants, we obtain an equation to determine the spontaneous magnetization as a function of the Cu dopant concentration and the hole carrier density. It is demonstrated that nonmagnetic Cu doped GaN can be of room-temperature ferromagnetism. The system＇s Curie temperature Tc can reach about 345 K with Cu concentration of 1.0% and hole carrier density of 5.0×10^19 cm-3. The results are in good agreement with experimental observations and indicate that ferromagnetism in this systems is tunable by controlling the Cu concentration and the hole carrier density.

关 键 词：Cu-doped GaN diluted magnetic semiconductor FERROMAGNETISM hole carrier density 

分 类 号：O471[理学—半导体物理]