Eur. Phys. J. B (2015) 88: 75
https://doi.org/10.1140/epjb/e2015-50491-1

Regular Article

First-principles study of electronic and magnetic properties in Co doped BaTiO₃

¹ School of Physics and Microelectronics, Hunan University, Changsha 410082, P.R. China
² College of Sciences, Jiliang University, Hangzhou 310018, P.R. China
³ Jiangsu Laboratory of Advanced Functional Materials, Department of Physics, Changshu Institute of Technology, Changshu 215500, P.R. China

^a e-mail: mqcai@hnu.edu.cn

Received: 20 July 2014
Received in final form: 19 December 2014
Published online: 25 March 2015

Abstract

The electronic and magnetic properties of Co doped BaTiO₃ have been investigated using the first-principle calculations within density functional theory. The nature of magnetism is mainly from the dopant Co atom with magnetic moment 3.15μ_B, suggesting the Co impurity atom with a high-spin configuration. With the increasing doping concentration, there exist mid-gap states at the Fermi level that increases the probability of electron transitions from valence band to conduction band. On the other hand, the O vacancy has a significant influence on the electronic and magnetic properties in doped BaTiO₃ systems. The presence of O vacancy leads to the elapse of system magnetism from 4.78μ_B to 1.0μ_B, indicating the transition of the spin configuration of Co atom from a high-spin state to a low-spin one. The results are in good agreement with the experimental observations.