Coherent octave-spanning mid-infrared supercontinuum generated in As_2S_3-silica double-nanospike waveguide pumped by femtosecond Cr:ZnS laser

-silica hybrid waveguide enables a ~100 pJ level pump pulse energy threshold for octave-spanning spectral broadening at a repetition rate of 90 MHz. Numerical simulations show that the generated supercontinuum is highly coherent over the entire spanning wavelength range. The results are important for realization of a high repetition rate octave-spanning frequency comb in the mid-infrared spectral region.