Magneto-Optical Study of Low-Temperature Phase Transition in Magnetite

Abstract
The magnetic polar Kerr effect for the visible and near infrared light is measured on synthetic single crystals of Fe 3 O 4 in the temperature range 90–300 K. The Kerr rotation angle undergoes a discontinuous change at the Verwey transition temperature, T V , near 120 K. The rotation angle vs wavelength curve in the visible range exhibits a blue shift below T V .