Multilayer optics for coherent EUV/X-ray laser sources

After a brief review of recent results achieved at Laboratoire Charles Fabry concerning high reflectivity mirrors, mirrors with enhanced spectral purity and broadband mirrors, we describe a new approach to design high efficiency multilayer mirrors for application on a broad spectral range. The main idea is to use 2 “spacer” materials (Aluminum and Scandium) in combination with a third material (Boron carbide or Silicon Carbide). We present several examples of design optimization using such multilayers. Finally, we show the first preliminary experimental results with Al/Sc/B4C and Al/Sc/SiC multilayers deposited by ion beam sputtering.