A cw room-temperature Ho,Tm:YLF laser pumped at 1.682 μm

We present the results obtained with a Ho,Tm:YLF crystal grown at a new crystal growth facility in Pisa. The optical quality of the sample has been tested by studying its performance as the active medium of a laser operating at 2.06 mum. We employed three different pump laser sources: a Ti:sapphire, a diode (both tuned at 793 nm) and, for the first time, a continuous-wave Co:MgF2 laser, tuned at 1.682 mum. At room temperature the best slope efficiency was 30 % in the case of "red" pumping, and 59 % in the case of "infrared" excitation. The typical lasing threshold is about 100 mW.