Growth, spectroscopic properties, and laser action of Yb:YPO 4 crystal

Good-quality single crystals of Yb:YPO4 were grown in a high-temperature solution. Polarized absorption and emission cross-section spectra were determined by use of a plate-shaped crystal of 1.8 mm in thickness. Efficient continuous-wave laser action was achieved under diode end-pumping conditions, with output coupling changed in a wide range of 0.5%−40%. A maximum output power of 3.62 W was produced with a 1.0 mm thick crystal, with an optical-to-optical efficiency of 36%.