Lattice engineering through Al-substitution leads to enhanced magneto-optical properties of Tb3(AlxGa1−x)5O12 single crystals

Abstract

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 Tb₃(Al_xGa₁)₅O₁₂ (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.