Eur. Phys. J. B (2013) 86: 284
https://doi.org/10.1140/epjb/e2013-30474-0

Regular Article

Enhance ferromagnetism by stabilizing the cation vacancies in GaN

¹ Departments of Physics and Electronics, Hengyang Normal University, Hengyang 421008, P.R. China
² Department of Applied Physics, Hunan University, Changsha 410082, P.R. China

^a e-mail: lmtang@hnu.edu.cn
^b e-mail: llwang@hnu.edu.cn
^c e-mail: keqiuchen@hnu.edu.cn

Received: 14 June 2012
Received in final form: 20 December 2012
Published online: 24 June 2013

Abstract

The magnetic properties related to cation vacancies in GaN are investigated by first-principles calculations. The results show that a neutral Ga-vacancy induces 3μ_B magnetic moment in GaN, but is difficult to form due to the high formation energy. It is found that the Ga-vacancy formation energy can be reduced by adding electrons with uniform compensating positive background charge, by nano-structure engineering, or by co-doping donor-like defects. The Ga-vacancy induced colossal magnetic moment in Gd-doped GaN can be modulated by co-doping the donor like defects. It is suggested that ferromagnetism enhanced by stabilizing the cation vacancies may be applied to other wide band-gap semiconductors as well.