Magneto-optical Faraday effect in dysprosium oxide (Dy₂O₃) based ceramics obtained by vacuum sintering

The method of self-propagating high-temperature synthesis of submicron powders with subsequent vacuum sintering was used to produce a series of optical ceramics based on dysprosium oxide (DyxY0.95−xLa0.05)2O3, where x=0.7, 0.85, and 0.9. The influence of ceramics composition on optical transmission of the obtained samples was investigated. The studied materials had several transparency windows in the visible 500–730 nm, near-IR 1900–2300 nm, and mid-IR 3500–7500 nm ranges. The dependence of the Verdet constant on wavelength in the 400–1940 nm range was measured for each ceramics composition, and analytical approximations were obtained. When Y and La dopants were used, the Verdet constant depended linearly on the concentration of Dy3+ ions, and its value in the visible wavelength range was about twice that of the analogous value for a terbium gallium garnet crystal. The high transmission and relatively high Verdet constant make the produced materials highly promising for fabricating Faraday devices for Tm3+ and Ho3+ lasers and for lasers emitting in the visible spectrum.