Pressure effect on spin-driven multiferroicity in a Y-type hexaferrite

Abstract

We have investigated the influence of pressure on the magnetoelectric multiferroicity of the Ba_1.5Sr_0.5Mg₂Fe₁₂O₂₂ hexaferrite under hydrostatic pressures up to 3.08 GPa. The spin-induced ferroelectricity is dramatically suppressed by pressure. The electric polarization and magnetoelectric coefficient at 3.08 GPa are reduced to about half of those at 0.12 GPa. With increasing pressure, the critical magnetic field of the transverse conical to longitudinal conical phase transition shifts toward higher fields and the magnetic phase temperatures shift to lower temperatures, indicating tunable exchange interactions by pressure. The suppression of spin-induced ferroelectricity by pressure in Ba_1.5Sr_0.5Mg₂Fe₁₂O₂₂ is ascribed to the weakening of the inverse Dzyaloshinskii–Moriya interaction based on the spin current model.