Effect of erbium concentration on the Verdet constant dispersion of LiY1.0-xErxF4 single crystal

Abstract

The dispersion of the Verdet constant of LiY1.0-xErxF4 crystals was evaluated from 190 nm to 500 nm for different doping concentrations of Er ions. A 15% doping concentration yielded a high Verdet constant of 54.5 rad/(T·m) at 193 nm. This value can be explained by the contribution of the diamagnetic term associated with LiYF4 and the paramagnetic term of the Er ions. Although the LiYF4 crystal yielded a lower value of −36.6 rad/(T·m) at 193 nm from Er-doped LiYF4, it can be used in the vacuum–ultraviolet region because of its high transmittance at wavelengths longer than 120 nm.