The rapid development of high power laser near 2 µm increases the demand of optical isolators and optical circulator that require materials with low optical absorption and high Verdet constant in that wavelength region. We have studied the magneto optical properties of three different kinds of chalcogenide glasses, Te2As3Se5, GeSe9, and Ge25As15S60, and Dysprosium doped borate glasses with different weight percentages from 60 wt.% to 75 wt.%. The Verdet constant of diamagnetic glasses is highly dependent on the dispersion of refractive index as a function wavelength and also absorption edge, while in the paramagnetic glasses the concentration of rare earth element ( Dy3+) plays the main role. The Verdet constant of both type of glasses decreases monotonically as a function of wavelength. The average resonant wavelength of Dy3+ glasses were found to be in the region of far UV while for Te2As3Se5, GeSe9, and Ge25As15S60 were 500, 330, 250 nm respectively. The Verdet constant of Dy3+ doped borate glass increases linearly as a function of Dy3+ concentration in 2 um region. The Verdet constant of chalcogenide glasses increase linearly as function of square of absorption edge wavelength. The highest Verdet constant in Dy glasses was measured to be -414 deg/T/m for 75 wt.% Dy3+ doped borate glass. The highest Verdet constant at 1940 nm was obtained to be 870 deg/T/m for Te2As3Se5 which is the highest Verdet constant reported in diamagnetic and paramagnetic glasses to the best of our knowledge. The figure of merit was found to be around 550 deg/T in 2 µm region for the telluride glass.
High power laser systems operating at mid IR wavelengths are required for medical applications, environmental monitoring, and military applications. All of these systems require optical isolators to avoid feedback into the pump laser cavity. We present measurements of the Verdet coefficient of germanate glass with Dy concentrations varying from 20-50% at wavelengths between .4 and 1.5 microns. The results indicate a linear increase of the Verdet coefficient with impurity concentration and a Sellmeier like dependence on wavelength.