Thermally induced effects in a faraday isolator on terbium sesquioxide (Tb2O3) ceramics

Abstract A traditional Faraday isolator on terbium sesquioxide (Tb2O3) ceramics was implemented, and the experimental studies of its operation at high-power laser radiation were performed for the first time. The degree of “cold” depolarization at low laser power was γ = 1.7∙10−5. The considered Faraday isolator ensured the isolation ratio better than 30 dB up to an average power of laser radiation of 90 W. The focal length of the thermal lens was 1.16 m (1/F = 0.86 1/m) at 90 W average power and spot diameter of 1.3 mm. Estimates were made and the potential for a further increase of maximum admissible power Pmax of Faraday isolators on the Tb2O3 ceramics was analyzed.