Ultraviolet generation with passively Q-switchedmicrochip lasers

First, second, third, fourth, and f ifth harmonics of the output of a f iber-pumped passively Q-switched Nd:YAG microchip laser have been obtained at pulse energies of 8.0, 3.5, 0.3, 0.7, and 0.01 microJ, respectively, in an optical head occupying a volume of less than 3 cm(3). This compact, economical all-solid-state source provides coherent subnanosecond multikilowatt infrared, visible, and ultraviolet pulses at repetition rates in excess of 10 kHz.