Broadband milliwatt-level pulse train beyond 6 μm from a femtosecond Yb oscillator

The spectral broadening properties of a standard SM980 fiber, combined with the large phase-matching bandwidth of 1-mm-thick LGS crystal, provide a simple and robust platform for generating broadband milliwatt-level pulse trains spanning 6 to 10 μm from a conventional Yb oscillator operating at a repetition rate of 80 MHz. This source is an effective solution for a wide range of vibrational spectroscopy experiments in the fingerprint region, both in the time and frequency domain.