High-power (> 400 mW) laser emission at 332 nm of frequency-doubled, optically pumped AlGaInP disk laser with an optimized quantum well structure

Semiconductor disk lasers (SDLs), also known as vertical-external-cavity surface-emitting-lasers (VECSELs) are an ideal choice to reach high output powers. Further advantageous characteristics [1] of this laser type, such as superior beam quality with a radial symmetric TEM00 beam profile, are provided by the external cavity, which also enables easy implementation of optical intra-cavity elements like frequency filters or frequency converting crystals. A further big advantage of VECSELs is given by the possibility of bandgap engineering. By proper adjustment of the semiconductor material and their composition, many different wavelength areas can be covered. The optimizaion of the quantim well (QW) arrangement should further lead to improved performance e.g. low threshold and high output power.