Octave-spanning mid-infrared pulses by plasma generation in air pumped with an Yb:KGW source.

Femtosecond mid-infrared (IR) supercontinuum generation in gas media provides a broadband source suited for time-domain spectroscopies and microscopies. This technology has largely utilized <100  fs Ti:sapphire pump lasers. In this Letter, we describe the first plasma generation mid-IR source based on a 1030 nm, 171 fs Yb:KGW laser system; when its first three harmonics are focused in air, a conical mode supercontinuum is generated that spans <1000 to 2700  cm^-1 with a 190 pJ pulse energy and 0.5% RMS stability.