Broadband dispersive Ge/YbF3 mirrors for mid-infrared spectral range

Abstract

Broadband dispersive mirrors operating in the mid-infrared spectral range of 6.5–11.5 μm are developed for the first time, to the best of our knowledge. The mirrors comprise Ge and YbF<inf>3</inf> layers, which have not been used before for manufacturing of multilayer dispersive optics. The design and production processes are described; mechanical stresses of the coatings are estimated based on experimental data; and spectral and phase properties of the produced mirrors are measured. The mirrors compensate group delay dispersion of ultrashort laser pulses accumulated by propagation through 4 mm ZnSe windows and additional residual phase modulation of an ultrashort laser pulse.