End-pumping Tm,Ho,Ce:NaY(WO4)2 crystal laser at 2.07 μm and the up-conversion repressed

We presented an infrared laser output at 2.07 μm with Tm,Ho,Ce:NaY(WO4)2 single crystal end-pumped by 795 nm laser diode at room temperature. The crystal was grown by the Czochralski method with the concentrations of 5 at.% Tm3+, 1 at.% Ho3+, and 30 at.% Ce3+. The highest output power was up to 0.2 W corresponding to the pumping power of 50 W and the threshold was about 40 W at 293 K. Especially, the introduction of Ce3+ brought about a novel phenomenon. End-pumping with the 795 nm LD, we surprisingly found the up-conversion was repressed heavily and the green emission disappeared thoroughly in Tm,Ho,Ce:NaY(WO4)2 crystal, which was particularly different from the crystal Tm,Ho:NaY(WO4)2, where the green emission was obvious and weakened the sensitized transition energy