Subpicosecond fiber-based soliton-tuned mid-infrared source in the 9.7-14.9 microm wavelength region.

We present a fiber-based mid-IR source of ultrafast laser pulses tunable in the 9.7-14.9 microm spectral region based on difference-frequency mixing between an Er:fiber laser and a first-order frequency-shifted soliton pulse. We have measured subpicosecond pulses at a repetition rate of 37 MHz, with a maximum power of 1.5 microW.