Efficient laser diode side pumped neodymium glass slab laser

The authors report efficient pulse operation of an Nd:glass slab laser-side-pumped by laser diode arrays. 7.5 mJ output and a slope efficiency of 29% were obtained with 35 nJ pump energy at 0.8 μm in 200 μs pulses. The wide absorption band at 0.8 and low laser loss in this phosphate glass allow for efficient pump light absorption and straightforward scalability to high power. The authors demonstrate 22% optical efficiency in a long pulse, multimode diode pumped laser oscillator based on a phosphate laser glass, LHG-8, highly doped with Nd ₂O₃. The strong and wide absorption bands in such phosphate glasses allow efficient pumping while somewhat relaxing the expensive wavelength selection requirements for laser arrays compared with crystal line host materials. With such materials, smaller slab thickness or rod diameters that are feasible with Nd:YAG can be used in the side-pumping geometry