Effect of Li doping on the electronic and magnetic properties of BiFeO₃ by first principles

Abstract

In the present work, the electronic and magnetic properties of Li doped BiFeO₃ (BFO:Li) are calculated using density functional theory (DFT). The exchange and correlation part of the energy functional is implemented through LSDA + U functional, where U is the Hubbard parameter which considers the localization of Fe d electrons. The obtained results suggest that Li doping induces weak ferromagnetism in BFO. The value of magnetic moment per unit volume of Li doped BFO is calculated to be 0.9992 ${\mathrm{\mu }}_{\mathrm{B}}$/cell. The value of bandgap of Li doped BFO (1.921 eV) is found to reduce considerably in comparison to pure BFO (2.24 eV). The decrease in the value of bandgap in BFO upon Li doping may be attributed to the appearance of electronic states in the forbidden region with respect to pure BFO.

KEYWORDS:

• BiFeO₃
• density functional theory
• Li doping
• electronic and magnetic properties