Photomagnetoelectric and magnetophotovoltaic effects in multiferroic BiFeO3
Résumé
A polarized light beam modifies the equilibrium tensors associated with any measurable property of a crystal. The light-induced linear magnetoelectric susceptibility and electric current density of bismuth ferrite (BFO) are investigated theoretically using their expansion in Wigner spherical functions. Under illumination, the interplay between magnetoelectric and photovoltaic properties yields the emergence in the paramagnetic and multiferroic phases of BFO of linear photomagnetoelectric tensor components changing sign in domains with opposite electric polarization or magnetization, and to magnetophotocurrents changing sense in opposite ferroelectric and magnetic domains.