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Microscopic modelling and experimental results on VECSELS for optical and THz applications

A microscopic theory is used to model the optical properties of semiconductor laser materials and modern devices. Typically, these devices are structured on the nanoscale such that any quantitative modelling requires a consistent quantum mechanical theory. In this talk, we show how such a many-particle approach can be used to compute the laser gain, absorption, photoluminescence as well as the radiative and Auger recombination processes. The predictive power of this modelling is demonstrated by detailed comparisons to quantitative experiments. In particular, so-called VECSEL (Vertical External Cavity Surface Emitting Laser) systems are analyzed. It is shown that systematic design studies allow for device optimization for a wide variety of different application conditions, such as high output power, emission at a particular wavelength, or low threshold [1–3].