闪锌矿Ga_(1-x)Cr_xN铁磁性的密度泛函理论(英文)  

Ferromagnetism in cubic Ga_(1-x)Cr_xN by density functional calculations

作　　者：熊志华[1] 孙振辉[1] 彭建飞[1] 李冬梅[1] 万齐欣[1] 刘国栋[1] 汪胜前[1] 施思齐[2] 

机构地区：[1]江西科技师范学院江西省光电子与通信重点实验室,南昌330013 [2]浙江理工大学物理系,杭州310018

出　　处：《功能材料与器件学报》2009年第3期269-274,共6页Journal of Functional Materials and Devices

基　　金：National Natural Science Foundation of China(Grant Nos,10564002,10604023,60767001);Qianjiang Talent Project of Zhejiang Province(Grant No.2007R10028);Science and Technology foundation of Jiangxi province Education Department((Grant No,2007281)

摘　　要：采用基于密度泛函的第一性原理方法计算了闪锌矿GaN掺Cr的电子结构和磁性。考虑不同掺杂浓度和位置,计算结果表明,Ga1-xCrxN呈现铁磁基态,Cr原子间是铁磁性耦合并团簇于N原子,Cr原子与最近邻N原子为反铁磁性耦合。我们采用双交换机制解释了磁性来源和机制。计算结果和最近闪锌矿GaN掺Cr的实验结果吻合。We report the results of a theoretical study of magnetic coupling between Cr atoms doped in cubic GaN. The calculations are within the framework of density functional theory. By varying the concen- tration of doped Cr atoms and the sites they occupy, the electronic structure and magnetic properties of Cr -doped cubic GaN are calculated. It is found that the ferromagnetic phase of Ga1 -xCrxN is energetically the most preferable state irrespective of the concentration and site occupation of the Cr atom. Cr atoms cluster around N and couple ferromagnetically, while the neighboring N atom is antiferromagnetically coupled to the Cr spin in the zinc blende Ga1-xCrxN. The origin of the ferromagnetism in the Cr - doped cubic GaN can he understood by double -exchange mechanism. The calculated results are consistent with the recent experimental discovery of ferromagnetism in Cr- doped GaN single cubic phase.

关 键 词：铁磁性 闪锌矿Ga1-xCRxN 密度泛函理论 

分 类 号：O482[理学—固体物理]