Half-metallicity and electronic structures for carbon-doped group III-nitrides: Calculated with a modified Becke-Johnson potential

Department of Physics, China Three Gorges University - Yichang, 443002, China

^(a) fansw1129@126.com

Received: 1 August 2016
Accepted: 29 September 2016

Abstract

The electronic structures and magnetism for carbon-doped group III-nitrides are investigated by utilizing the first principle method with the modified Becke-Johnson potential. Calculations show that carbon substituting cations (anions) would induce the group III-nitrides to be paramagnetic metals (half-metallic ferromagnets). Single carbon substituting nitrogen could produce 1.00μ_B magnetic moment. Electronic structures indicate that the carriers-mediated double-exchange interaction plays a crucial role in forming the ferromagnetism. Based on the mean-field theory, the Curie temperature for carbon-doped group III-nitrides would be above the room temperature. Negative chemical pair interactions imply that carbon dopants tend to form clustering distribution in group III-nitrides. The nitrogen vacancy would make the carbon-doped group III-nitrides lose the half-metallic ferromagnetism.