The electronic, magnetic and optical properties of double perovskite A2FeReO6 (A = Sr, Ba) from first principles approach

A density functional theory (DFT) employing generalized gradient approximation (GGA) and modified Becke Johnson (TB-mBJ) potential have been used to study the electronic, magnetic and optical properties of A(2)FeReO(6) (AFRO). The presence of indirect band gap of majority electrons at E-F and the conducting behaviour of minority electrons predicts these materials to be a half metallic ferrimagnets. The GGA band gaps are enhanced with the implementation of a new electron exchange semilocal potential called TB-mBJ. The real and imaginary parts of dielectric function, refractive index, absorption coefficient and reflectivity are calculated. The inter-band transitions to the optical properties are analyzed with the band structures. (C) 2015 Elsevier B.V. All rights reserved.