铁磁材料GdN的电子结构和磁学性质的理论研究

作为寻找新型自旋电子学功能材料的尝试，文章详细研究了稀土化合物GdN的电子结构和磁学性质，通过第一性原理的理论计算，作者发现该材料的导电性质随体积增加有很大变化：从半金属态到准金属态，最后成为半导体．同时，施加压力能改变其载流子浓度和位于多数自旋态的电子和空穴的迁移率．对其磁交换参数随品格常数变化的进一步研究和蒙特卡罗模拟表明，这个铁磁体系的居里温度可以通过加压或掺杂得到进一步提高，从而成为很有实用价值的自旋电子材料．

Theoretical studies on the electronic and magnetic properties of GdN

As an attempt to find suitable materials for spintronic devices we have investigated the electronic structure and magnetic properties of rare-earth compound GdN as a function of unit cell volume. Based on a first-principles calculation we observe that there is a transformation in the conduction properties associated with the volume increase, first from half-metallic to semimetallic, then ultimately to semiconducting. We show that applying stress can alter the carrier concentration as well as mobility of the holes and electrons in the majority spin channel. In addition, we find that the exchange parameters depend strongly on lattice constant, thus the Curie temperature of this system can be enhanced by applying stress or doping impurities. This demonstrates that GdN is a potentially excellent spintronic material.