Efficiency of transverse pumping of a solid-state pulsed Nd:YAG laser by laser diode arrays

A Nd³⁺:YAG laser with a cylindrical active element transversely pumped by quasi-continuous laser-diode arrays located around its side surface is studied experimentally. The developed pumping modules with symmetric and asymmetric geometries provide the differential efficiency of 48% and 55% for multimode free-running lasing upon pumping of elements of diameter 3 and 5 mm, respectively. Under the conditions corresponding to this efficiency of utilisation of radiation emitted by laser diode arrays, laser pulses with energy of 28 and 55 mJ are generated in the Q-switching mode.