Preparation and characterization of transparent magneto-optical Ho2O3 ceramics

Transparent magneto-optical Ho2O3 ceramics were successfully prepared with an in-line transmittance of similar to 73% at the wavelength of 1000 nm (similar to 90% of the theoretical transmittance of Ho2O3 single crystal) and an average grain size of similar to 28 mu m. The ceramics were fabricated using sulfate-exchanged nitrate-type layered rareearth hydroxide as the precipitation precursor at a relatively low sintering temperature of 1700 degrees C. The layered compound exhibited nanosheet morphology and fully collapsed into a round oxide powder with an average particle size of similar to 48 nm by pyrolysis. Calcination temperature for Ho2O3 powder significantly affected the optical quality of the sintered body and the optimum calcination temperature was found to be 1050 degrees C. The transparent magneto-optical Ho2O3 ceramics displayed wavelength-dependent Verdet constants of -180, -46, and -20 rad/Tm at 632, 1064, and 1550 nm, respectively. Thus, the Ho2O3 ceramics show good potential for applications in high-power laser systems.