Magnetoelectric Effects of Fe₃O₄at 4.2 K

Abstract

Magnetoelectric effects of magnetite at 4.2 K were measured by applying magnetic field with both dc and ac methods. Analyses of the signals indicate that the magnetic crystal symmetry at 4.2 K is nearly monoclinic but exactly triclinic. The results of ac measurements at different magnitude of the applied magnetic field suggest that the electric poralization is induced mainly by the rotation of the magnetization. The polarization along the b -axis, however, can not be explained by this mechanism only.