Los Andrei, Los Victor
ISS Ltd, Semiconductors and Circuits Lab, 15 Bozhenko Street, 03680 Kiev, Ukraine. Freescale Semiconductor Incorporated, 15 Bozhenko Street, 03680 Kiev, Ukraine. Institute of Magnetism, 36-b Vernadsky Boulevard, 03142 Kiev, Ukraine.
J Phys Condens Matter. 2009 May 20;21(20):206004. doi: 10.1088/0953-8984/21/20/206004. Epub 2009 Apr 24.
Electronic properties of 3C silicon carbide with substitutional transition metal impurities are calculated using an ab initio full-potential linearized augmented plane wave technique. It is shown that transition metal atoms in an SiC host may exist in both magnetic and nonmagnetic states. For different impurity species, the transition from the nonmagnetic to the magnetic state and the corresponding change of the atomic magnetic moments may take place either gradually as the volume of the unit cell changes or when the energy gap between the two states is overcome. The magnetic and nonmagnetic solutions are characterized by significantly different unit cell geometries, which are analysed in detail. Magnetic ordering is studied for a number of transition metal impurities in SiC and mean-field estimates of the Curie temperature are given. Calculated densities of states are used to analyse the nature of the exchange interaction between the impurities. Some properties of transition metal impurities are compared for 3C and 4H silicon carbide substitution.
采用从头算全势线性缀加平面波技术计算了含替代过渡金属杂质的3C碳化硅的电子性质。结果表明，SiC主体中的过渡金属原子可能以磁性和非磁性两种状态存在。对于不同的杂质种类，从非磁性状态到磁性状态的转变以及原子磁矩的相应变化，可能会随着晶胞体积的变化而逐渐发生，也可能在两种状态之间的能隙被克服时发生。磁性和非磁性解的特征是具有明显不同的晶胞几何结构，对此进行了详细分析。研究了SiC中多种过渡金属杂质的磁有序，并给出了居里温度的平均场估计值。利用计算得到的态密度来分析杂质之间交换相互作用的性质。比较了3C和4H碳化硅替代中过渡金属杂质的一些性质。
