Magnetoelectric coupling in polycrystalline FeVO 4
Résumé
We report coupling between magnetic and electric orders for antiferromagnetic polycrystalline FeVO4 in which magnetism-induced polarization has been recently found in noncollinear antiferromagnetic state below the second antiferromagnetic phase transition at TN2≈15.7 K. In this low symmetry phase space group P¯1, the magnetic field dependence of electric polarization evidences a clear magnetoelectric coupling in the noncollinear spin-configured antiferromagnetic phase. The discontinuity of magnetodielectric effect observed at the vicinity of the polar to nonpolar transition evidences competition between different magnetodielectric couplings in the two different antiferromagnetic states. The existence of thermal expansion anomaly near TN2 and magnetostriction effect support magnetoelastically mediated scenario of the observed magnetoelectric effect.