29 Mar 2021
Alexandrite (Cr3+:BeAl2O4, chromium-doped beryllium aluminate) is a laser gain material used in solid-state lasers for applications such as dermatology and Lidar, etc. Alexandrite is produced via the Czochralski growth method. It has a thermal shock resistance five times that of Nd:YAG and a wide emission wavelengths typically between 710nm and 800nm – in many cases around 755nm.
It is possible to make broadly wavelength-tunable lasers based on alexandrite. Alexandrite is anisotropic, the absorption and gain properties strongly depend on the direction of pump light’s polarization. This together with the strong birefringence of the material makes it easy to obtain linearly polarized emission with low depolarization losses.