2 μm MOPA Laser Based on Cryogenically Cooled Tm:Y2O3 Transparent Ceramic

Pulsed high average and peak power (HAPP) lasers emitting around 2 μm have broad numbers of applications in the field of science and technology, such as medical surgery, remote sensing, optical communication, etc. [1] . To achieve efficient 2 μm HAPP lasers, thulium (Tm 3+ ) doped active medium is a smart choice because it can be pumped using commercially available AlGaAs laser diodes. In addition, as a prerequisite for HAPP laser development, cooling the active media to cryogenic temperature is a commonly used method, which suppresses the thermal issues and enhance the material properties. Based on these facts, cryogenically cooled Tm 3+ -doped Y 2 O 3 transparent ceramic is chosen as an active medium among various promising candidates. The cryogenic properties of this material have been studied and presented in our previous work [2] .