Ba_2Ti_2Fe_2As_4O的电子结构和磁性的第一性原理计算  

FIRST PRINCIPLES CALCULATIONS THE ELECTRONIC STRUCTURE AND MAGNETISM OF Ba_2Ti_2Fe_2As_4O

作　　者：王广涛[1] 易霞[1] 石贤彪 

机构地区：[1]河南师范大学物理与电子工程学院,河南新乡453007

出　　处：《低温物理学报》2016年第2期85-90,共6页Low Temperature Physical Letters

基　　金：国家自然科学基金(No.11274095)资助的课题

摘　　要：基于第一性原理计算,我们研究了Ba_2Ti_2Fe_2As_4O电子结构和磁性.Fe原子处于条纹状反铁磁态时最稳定,自旋磁矩约为2.2μB,而Ti的磁矩几乎为零.因此Fe_2As_2层在125K附近磁化系数转变时起主要作用.我们预测在超导状态将会有大于0.2 e的电子转移到Fe_2As_2层,并且超导发生在Fe_2As_fz2层.Based on the first-principles calculations, we investigate the electronic and magnetic properties of the self-doping compound Ba2 Ti2 Fe2 As4 O. The Fe atoms in the stripe antiferromagnetic configure is more stable than other magnetic states. The spin moment on Fe atom is about 2. 2μB, but the moment on Ti atom almost as 0μB. So the Fe2As2 layers takes major role in the anomaly transition in resistivity and magnetic susceptibility around 125K. We predicate that there will be more than 0. 2 electron transfers to the the Fe2 As2 layers in the superconductive state, and the superconductivity takes place in the Fe2As2 layers.

关 键 词：第一性原理计算 费米面嵌套 超导 

分 类 号：O511.3[一般工业技术—材料科学与工程]