Watt-level mid-infrared radiation via self-seeded difference-frequency generation from a pre-chirp managed femtosecond Yb-fiber amplifier.

We obtained over 1 W average power at ∼3550  nm wavelength via self-seeded difference-frequency generation (DFG) through a 5 cm long periodically poled MgO-doped lithium niobate crystal. The pump and signal sources are derived from the identical pre-chirp managed femtosecond Yb-fiber amplifier with sub-100-fs pulse duration and 84 MHz repetition rate for simple synchronization. This result is believed to be among the highest-average-power, femtosecond mid-infrared radiation obtained via DFG.