Generation of broadband 17-μJ mid-infrared femtosecond pulses at 3.75 μm by silicon carbide crystal.

In this contribution, we report the generation of 17-μJ mid-infrared (MIR) pulses with duration of 70 fs and bandwidth of 550 nm centered at 3.75 μm at 1-kHz repetition rate, by a two-stage femtosecond optical parametric amplifier utilizing 4H-silicon carbide crystal as the nonlinear medium. The crystal is selected as it processes orders of magnitude higher damage threshold than traditional MIR nonlinear crystals, and it supports extreme broad parametric bandwidth. With its distinguished features such as MIR central wavelength, ultra-broad bandwidth, self-stable carrier-envelope phase, and potential for energy scaling, this kind of MIR source holds promise for new approaches to extreme short isolated attosecond pulse generation as well as MIR spectroscopy applications.