Magnetoelectric, photovoltaic, and magnetophotovoltaic effects in KBiFe2O5

Multiferroic materials are intensively investigated as potential candidates for a new generation of solar cells, due to the coexistence in their phases of ferroelectricity and magnetic order with low band gap. However, symmetry considerations, which determine the interplay between the magnetoelectric and photovoltaic properties of a light irradiated multiferroic crystal, are not fully taken into account in the current theory of the photovoltaic effect. Here the remarkable photovoltaic and magnetophotovoltaic effects occurring in the multiferroic phase of KBiFe2O5 are described using a theoretical approach that takes directly into account the crystal and light beam wave symmetries.