CAJ | 학술논문

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.
채용기우밀도범함적제일성원리방법계산료섬자광GaN참Cr적전자결구화자성.고필불동참잡농도화위치,계산결과표명,Ga1-xCrxN정현철자기태,Cr원자간시철자성우합병단족우N원자,Cr원자여최근린N원자위반철자성우합.아문채용쌍교환궤제해석료자성래원화궤제.계산결과화최근섬자광GaN참Cr적실험결과문합.
We report the results of a theoretical study of magnetic coupling between Cr atoms doped in cu-bic 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-xCrx N 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 cou-pled to the Cr spin in the zinc blende Ga1-xCrx N. The origin of the ferromagnetism in the Cr -doped cu-bic GaN can be understood by double - exchange mechanism. The calculated results are consistent with the recent experimental discovery of ferromagnetism in Cr - doped GaN single cubic phase.