Magneto-optical effects in ferrofluids at near millimetre wavelengths

Abstract

The results of experiments aimed at establishing the origin of near millimetre wavelength magneto-optical effects observed in various ferrofluids are presented and discussed. These microscopic effects are probed at the macroscopic level by using an a.c. magnetic field to impose polarization modulation on near millimetre wave radiation propagating through such fluids. The results indicate that the basic mechanism is Néel rotation of the magnetic moment within each component magnetic particle of the fluids.