High repetition rate, high peak power, diode pumped Tm:YLF laser

Abstract

The room-temperature, water-cooled, diode pumped Tm:YLF laser head was elaborated and examined. For pumping the fiber coupled (0.2 mm core diameter) 25-W laser diode bar emitting at 792-nm wavelength was deployed. Near 5 W of CW output power and 25% slope efficiency was demonstrated in a short, 70-mm long resonator. Tuning in 1845–1935 nm wavelength range by means of 2-plate Lyot filter was demonstrated only in free-running regime. The fused silica acousto-optic modulator with above 80% diffraction efficiency for 25-W power of RF was deployed as the Q-switch for such a laser. In the best case of Q-switching regime, up to 10-mJ output energy with 47-ns pulse duration, 220 kW peak power was demonstrated for 133 Hz. For higher repetition rate of 2 kHz, 12 kW peak power with 2.5 W of average power was achieved.