Lattice engineering through Al-substitution leads to enhanced magneto-optical properties of Tb₃(Al_xGa_1-x)₅ O₁₂ single crystals

High-performance magneto-optical materials are in urgent demand for high-power Faraday isolators. The traditional Tb3Ga5O12 crystal presents a relatively low Verdet constant and large absorption coefficient, which makes it difficult to meet the continuous development of high-power lasers. In this work, novel Tb-3(AlxGa1)(5)O-12 (TAGG) single crystals are grown by the Czochralski method. High-quality TAGG crystals with Al-substitution of up to 75% are obtained for the first time. The optical, thermal, and magneto-optical properties are significantly enhanced through high Al incorporation. This work demonstrates that the highly Al-substituted TAGG single crystals are remarkable magneto-optical materials for Faraday isolators.