6-mJ, 4-ns Pulse Generation at 2.09 $μ$m from a Diode-Pumped Ho:YAG Thin-Disk Laser

A holmium-doped yttrium aluminum garnet (Ho:YAG) thin-disk was experimentally investigated under Q-switching and cavity-dumping operation schemes, pumped by a 1.9 $μ$m laser-diode (LD). The laser generated pulses at 2090 nm with energies more than 6 mJ and pulse duration down to 3.8 ns, corresponding to a peak power of 1.6 MW with near-diffraction-limited beam quality. The compact and robust system was used for laser-induced breakdown spectroscopy (LIBS) experiments, demonstrating its practical usability. These results represent, to the best of our knowledge, the first demonstration of a Ho:YAG thin-disk laser providing MW peak-power in nanosecond regime.