QD MIXSEL

Semiconductor based light sources are the most efficient light emitting devices and have successfully been used for a huge variety of applications. However, there are still areas, where the semiconductor approach is not fully exploited. Although semiconductor lasers are dominating the market for optical communication, for the new generation of high-capacity coherent communication, frequency comb generation is mainly based on bulky conventional solid-state or fiber lasers due to the difficulties to combine supercontinuum generation with high enough peak powers. However, based on an integrated concept of vertical external cavity surface emitting lasers (VECSEL) with a semiconductor saturable absorbing mirror (SESAM), which forms a so-called mode-locked integrated external-cavity surface emitting laser (MIXSEL), there is a realistic chance to realize a semiconductor based very compact ultra-short high-power fs laser source for frequency comb generation in the optical domain. In particular by using quantum dot (QD) gain and absorber material, the material properties can be tailored over a wide range by additional geometry based degrees of freedom, which should allow to design and operate MIXSEL on the sweet spot of device operation optimizing the device performance well beyond existing technologies.

Joint project in frame of DFG international research group (D-A-CH + Israel) with ETH Zürich, Switzerland and with Israel Institute of Technology, Technion, Haifa.