Magnetization-odd nonreciprocal reflection of light from the magnetoelectric-ferromagnet LiFe5O8

Circular dichroism, which changes sign under magnetization reversal and exhibits a 120 degrees periodicity, is observed in the reflection of light from the (111) plane of a noncentrosymmetric LiFe5O8 crystal in the transverse geometry k perpendicular to M, where the linear Kerr effect is forbidden. It is shown that this phenomenon is due to the manifestation of optical magnetoelectric susceptibility and a Kerr effect of third order in the magnetization. The spectral dependences of the circular dichroism in the range 1.4-3.1 eV show that this phenomenon is of a resonance character. (C) 1997 American Institute of Physics.