Efficient Nd:YAG laser end-pumped by a 1 cm aperture laser-diode bar with a GRIN lens array coupling

A 10-W laser-diode bar, a multistripe monolithic laser-diode array, has been used to end-pump Nd:YAG. Twenty beams emitted from 20 stripes, spaced 500 mu m apart, of a 1-cm linear diode array were collimated by a 1-cm-wide lens array consisting of 20 GRIN (graded-index) lenses with a width of 500 mu m to pump the Nd:YAG facet. The maximum Nd:YAG CW output power at 1064 nm of 3.24 W CW was obtained at 8.6 W incident pump power with a total electrical-to-optical conversion efficiency of 10.1%, a threshold of 0.6 W, a maximum slope efficiency of 45%, and a single-lobed spatial mode.<
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