Laser pumping of Ho-, Tm-, Er-doped garnet lasers at room temperature

Laser pumping of Ho-, Tm-, and Er-doped garnets at room temperature is reviewed. Laser pumping of Tm (1860 nm), Ho (2090 nm), Er (1650 nm, 2710 nm) is possible with argon ion, krypton ion, and dye lasers. In Tm,Ho:YAG, efficient CW laser oscillation at 300 K is achieved under diode laser pumping. Er and Tm garnets might be pumped with diode lasers too. The highest slope efficiency of 41% is observed in Cr,Tm,Ho:YSGG under krypton laser pumping, demonstrating the efficient downconversion in this material. Red pump light is converted to the infrared spectral region at a quantum efficiency of nearly 2. >