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 YbF3 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.