Increasing the output power of Nd:YAG's 4F3/2→4I9/2 quasi-four-level transition is attractive for providing a highradiance
source with a wavelength below 1micron for applications at the life sciences interface, ranging and sensing, or
as a vital element for next-generation display technologies, when frequency converted into the blue-green part of the
visible spectrum. Reabsorption losses at the lasing wavelength combined with a relatively low stimulated emission crosssection
and competition with the much stronger 1.06 micron transition, demands a configuration with high pumping
intensity, comparable to the pump saturation intensity at 808 nm, to achieve efficient operation. However, even with the
availability of increasingly bright diode-lasers, the thermal deficit of the excitation cycle and the thermo-optic properties
of the YAG host medium currently limit the achievable output power at 9xx nm. Presented here is a double-clad planarwaveguide
Nd:YAG laser, operating at a lasing wavelength of 946 nm with an output power in the 100 W regime and
better than 50% optical to optical conversion efficiency. The enhanced thermal management characteristics of the
waveguide structure have enabled power-scaling well beyond that possible in a bulk laser configuration. These
advantages and further power-scaling possibilities will be discussed.
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