CPM Seminar

Electric polarization, magnetic order and Berry phase in multiferroics

Reza Nourafkan

Université de Sherbrooke

The search for materials with strong magneto-electric coupling requires an understanding of intertwined magnetic and ferroelectric orders. The so-called Berry phase approach for spontaneous polarization is a single-electron theory which does not allow calculation of electric polarization of correlation-driven insulators. Our generalization of the Berry phase approach to the case of interactions allows us to compute the electric polarization of a Mott insulator from first principles and to understand how the ferroelectric moment at high temperature is modified by the onset of magnetic order at lower temperature.