Theory of the photovoltaic and photo-magneto-electric effects in multiferroic materials
Résumé
Multiferroic materials are presently intensively investigated as potential candidates for a new generation of solar cells. We propose an approach to the photovoltaic effect that takes directly into account the crystal and light beam wave symmetries. it is based on an expansion in Wigner spherical functions and it allows predicting any light-induced crystal tensor. It permits to describe the angular variations of photo-induced effects including photovoltaic, photomagnetic, photogalvanic, photoelastic or optic rectification effects. Special attention is paid to time and space reversal symmetry breakdowns. Application to a number of photo-effects in LiNbO3 is worked out.