High efficiency 165 W near-diffraction-limited Nd:YVO(4) slab oscillator pumped at 880 nm

We demonstrate a compact, efficient Nd:YVO(4) stable-unstable hybrid slab oscillator that was partially end pumped at 880 nm. A maximum output power of 165 W at 1064 nm was obtained with an optical-to-optical efficiency from absorbed pump power to laser output of up to 60% and a slope efficiency of up to 66%. The beam propagation factors M(2) were 1.7 in the stable direction and 1.4 in the unstable direction without sidelobes.