Verdet constant dispersion of magnesium fluoride for deep-ultraviolet and vacuum-ultraviolet Faraday rotators

The Verdet constant dispersion in magnesium fluoride (MgF₂) crystals was evaluated over a wavelength range of 190-300 nm. The Verdet constant was found to be 38.7 rad/(T·m) at a wavelength of 193 nm. These results were fitted using the diamagnetic dispersion model and the classical Becquerel formula. The fitted results can be used for the designing of suitable Faraday rotators at various wavelengths. These results indicate the possibility of using MgF₂ as Faraday rotators not only in deep-ultraviolet regions, but also in vacuum-ultraviolet regions owing to its large bandgap.