Monolithic unstable-resonator Q-switched solid-state laser with large Fresnel number

摘要

We report the operation of a diode-pumped monolithic Q-switched unstable-resonator solid-state laser with a large Fresnel number. The unstable-resonator is found to be effective in suppressing the spatial and temporal instability of the lasing mode. The monolithic Cr,Nd: YAG laser with a Fresnel number of 1800 generates 2.15-mJ, 2-nanosecond pulses in single transverse mode and single longitudinal mode. The observed modal characteristics are consistent with a numerical calculation based on a simulation of beam propagation.