Single-frequency, end-pumped Nd:YLF laser excited by a 12-mJ diode-laser array

We describe the operation of a diode-laser-pumped, end-pumped Nd:YLF laser that utilizes a 12-mJ, 60-W, quasicw diode-laser bar. Multilongitudinal-mode, TEM(00) pulse energies of greater than 2 mJ have been observed, with corresponding Q-switched peak output powers in excess of 118 kW. The incorporation of a prelase Q-switching technique has seen single-longitudinal-mode peak powers in excess of 90 kW continuing to be achieved. The low-threshold operation at 1.539 microm of a singly resonant KTP optical parametric oscillator pumped by this source is also reported.