PECS · Powerful and Efficient EUV Coherent Light Sources

The interest in and hence the need for coherent short-wavelength (EUV spectral range) laser sources is rapidly increasing. Potentially, such sources will allow for novel approaches in fundamental science, metrology, imaging, spectroscopy and might even enable new lithographic production techniques. One example is Atto-Science, one of the groundbreaking topics in physical science of the next decade. High harmonic generation (HHG) in noble gases is considered as the most suitable technique to generate spatially coherent EUV light. Unfortunately, the conversion efficiency of HHG is rather small. Furthermore, conventional ultra-short pulse laser sources required for HHG are limited in average power due to thermo-optical problems, therefore, the resulting EUV radiation is characterized by an extremely low number of photons per unit time (average power). Consequently, all the applications of EUV radiation suffer from the lack of powerful coherent light sources in this interesting spectral range, which results extremely long integration or processing times. Ultimately this lack of power make current EUV sources be considered as laboratory curiosities without any relevance for real world applications. The goal of the proposed project is to investigate novel methods to increase the efficiency and the average output power of HHG based EUV light sources. Of outmost importance is the development of efficient, compact and powerful (>3 kW average power) high peak power (>100 MW) ultra-short pulse (<200 fs) laser systems to drive the HHG process. Fiber based amplifiers have the potential to fulfil this parameter range in a compact und ultra-stable manner allowing the generation of EUV radiation outside a specially protected laboratory environment. In summary, the goal of the proposed project is the development of efficient and powerful tailored, meaning application-oriented, EUV light sources.