Role of the Dzyaloshinskii-Moriya interaction in multiferroic perovskites

With the perovskite multiferroic RMnO3 (R = Gd, Tb, Dy) as guidance, we argue\nthat the Dzyaloshinskii-Moriya interaction (DMI) provides the microscopic\nmechanism for the coexistence and strong coupling between ferroelectricity and\nincommensurate magnetism. We use Monte-Carlo simulations and zero temperature\nexact calculations to study a model incorporating the double-exchange,\nsuperexchange, Jahn-Teller and DMI terms. The phase diagram contains a\nmultiferroic phase between A and E antiferromagnetic phases, in excellent\nagreement with experiments.\n