Research Progress on High-Melting-Point Rare Earth Oxides Laser Crystals
High-melting-point rare earth oxides,due to their advantages of high thermal conductivity,high mechanical strength,low phonon energy,and high cation site density,exhibit characteristics such as large segregation coefficients,strong electron-phonon coupling,and multiple lattice sites.These properties have made them a hot topic of research in high-power,ultrafast,and infrared laser crystals.However,their high-melting-points,particularly for sesquioxides(~2 450 ℃),pose significant challenges for crystal growth.Though being reported decades ago,the development of sesquioxide crystals remains in its early stage.In recent years,breakthroughs in various crystal growth techniques have been achieved,leading to a diversification of rare earth ion-doped laser research.This paper reviews the advantages of high-melting-point rare earth oxides,recent advancements in crystal growth,and the progress in laser performance across the infrared 1,2 and 3 μm wavelength bands.