High power semiconductor disk laser with monolithically integrated pump lasers

Abstract

Semiconductor disk lasers have attracted a lot of interest in the last few years due to high output power combined with good beam quality and possible wavelength engineering. One of the disadvantages is the need for external optical pumping by edge-emitting semiconductor lasers that increase packaging effort and cost. Therefore, semiconductor disk lasers with monolithically integrated pump lasers would be of high interest. We report on a novel design and experimental realization to monolithically integrate pump lasers with a semiconductor disk laser in a one-step epitaxial design. By careful design of integrated pump lasers and stacking sequence, it is possible to efficiently excite vertical emitter areas with different mesa sizes. First results are shown at 1060 nm emission wavelength with high output power out of mesa diameters of 100 μm to 400 μm. The devices can be conveniently characterized on a wafer level using dry-etched pump laser facets. In pulsed operation 1.7W out of a 100 μm diameter mesa and 2.5W out of a 200 μm diameter mesa are demonstrated. Additionally, more than 0.6W in cw operation using a 400 μm structure were achieved. In summary, an innovative approach for truly monolithic integration of a semiconductor disk laser with pump lasers has been pioneered.