Experimental demonstration of broadband femtosecond optical parametric amplification based on YCOB crystal at near critical wavelength degeneracy

Broadband optical parametric amplification (OPA) in the near-infrared region (1.3–1.8μm) is demonstrated in YCOB crystal pumped by 1kHz Ti:sapphire based femtosecond laser at near critical wavelength degeneracy phase matching condition at first time. The gain bandwidth is closed to BIBO or BBO crystal OPA gain bandwidth. The energy obtained with 3.5mm-thick YCOB reached 20μJ with RMS 1.9%. After second harmonic generation, 17.6fs pulse is obtained, and the pulse compressibility is demonstrated. •Broadband amplification at 1600nm at degeneracy utilizing YCOB is demonstrated.•This is the first use of YCOB for femtosecond regime OPA.•YCOB can be potentially applied as terawatt class long wavelength driving source.