Multiferroicity in cycloidal spiral spin magnet β-CrPO4

Abstract We prepared the high quality polycrystalline β -CrPO 4 with the cycloidal spiral spin magnetic structure. The multiferroicity is investigated by means of magnetic, heat-capacity, dielectric and ferroelectric polarization measurements. At the Neel temperature T ∼23 K, it is the transition into a spiral magnetic ordered phase, there is an anomaly in the dielectric and heat-capacity data, and the ferroelectric polarization appears. The ferroelectric polarization can be attributed to the cycloidal spiral magnetic ordering, which coincides well with the inverse Dzyaloshinskii-Moriya interaction scenario or the spin-current scenario. The magnitude of ferroelectric polarization decreases with increasing the applied magnetic field, which indicates there is the strong coupling between ferroelectric polarization and magnetism in β -CrPO 4 .