Investigation of nonlinear stimulated emission in optically excited dielectrics
The nonlinear stimulated emission of ultraviolet light in a piece of optically excited – and thus metalized – glass that usually absorbs light is counterintuitive to what has been known for many decades about light-material interaction. However, this is exactly what was recently experimentally observed for the first time. Although a preliminary explanation and model describing the effect of laser amplification in excited dielectrics (LADIE) exists, a manifold of questions about fundamental processes like the universality, the potential of nonlinear light amplification and how giant-band-gap-renormalization in dielectrics works remain unanswered. In this project, a thorough investigation of the novel phenomenon and the associated rare nonlinear stimulated emission will be initiated. On the one hand, this study is based on femtosecond spectroscopy, deploying pump-probe experiments, utilizing light-conversion and pulse-shaping techniques that will be applied to a large variety of custom-made samples. On the other hand, the experimental studies will be complemented by advanced theoretical modelling of the material excitation that will be extended towards incorporating a proper description of the new mechanisms. The investigation of the LADIE effect will most likely open up an entirely new scientific field with many new surprises in store and the potential for novel derived applications. Its perspective is a revolution in laser technology, building high power nonlinear laser amplifiers in a huge variety of band-gap materials, which has a clear interdisciplinary aspect to semiconductor and optoelectronic research (i.e. telecommunication hardware), biophysics (cell surgery, nonlinear microscopy) and nonlinear optics in general.