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Highly efficient ultra-low threshold miniature cerium fluoride lasers generating sub-nanosecond pulses at 287nm and 311nm

Ultraviolet (UV) miniature cerium fluoride lasers have been demonstrated using a low cost, frequency-quadrupled microchip Nd:YVO4 pump laser. The concept of miniature configuration of the cavities was shown to improve the laser performance in the low pump power region. Using a 10 μJ, 266nm pump pulse, we have obtained output energies of 3.5μJ at 287nm and 0.65 μJ at 311nm. The slope efficiencies were 45% and 35%, and the pump thresholds 2 μJ and 0.8 μJ respectively. Tunable operation of these lasers provides a simple compact wavelength converter from 266 nm to 282-333 nm.