Investigations of pulsed Nd:YAG laser with diode-laser bars side-pumped rod geometry.

An experimental studing of Nd:YAG rod side-pumping with quasy-cw laser-diode bars as a function of the laser rod and the pumping submount parameters was carried. We have found that the side-pumped-of-rod geometry without coupler optics between the laser diodes and the laser rod provides sufficiently high slope and optical efficiencies of Nd:YAG laser. Utilizing the concentric pumping arrangement with eight laser diode bars maximum optical efficiencies of 50% and 45% in long pulse mode was obtained when 5-mm and 4-mm-diameter Nd:YAG (1.2% at) rods respectively were used. In Q-switched operation Nd:YAG laser with this pumping sheme and 5-mm-diameter (1.2% at) rod had an output of 23 mJ in multimode 10 ns pulse when output coupler was of 60%.