DIODE-PUMPED 1.4-W TM3-M(GDVO4 MICROCHIP LASER AT 1.9 MU)

GdVO4 as a host for thulium has several advantages for diode pumping i n comparison with other crystals, The absorption cross section of thul ium in GdVO4 is considerably stronger and broader than in YAG and YLF, and the spectrum is shifted closer to the emission wavelength of comm ercially available AlGaAs laser diodes. In our paper, we report on a d iode-pumped monolithic Tm3+(6.9 at.%):GdVO4 microchip laser at 1.9 mu m A maximum output power of 1.4 W is achieved. Two different arrangeme nts for cooling the crystal are discussed. Furthermore, the input-outp ut curves under Ti:sapphire pumping are compared for different pump wa velengths, Slope efficiencies of 58%, clearly exceeding the Stokes lim it of 41%, are achieved.