Generation and parametric amplification of broadband chirped pulses in the near-infrared

We demonstrate generation and optical parametric amplification of broadband chirped pulses in the range of 1.8-2.5 mu m. The setup is built around Ti: sapphire oscillator as a seed source and 1 kHz Nd: YAG laser system as a pump source. Visible broadband seed pulses are temporally stretched and amplified in a non-collinear optical parametric amplifier before being mixed with fundamental harmonic of the pump laser. Difference frequency generation between positively-chirped broadband pulses centered at 0.7 mu m and non-chirped narrowband pulses at 1064 nm produces negatively-chirped wide spectral bandwidth pulses in the infrared. After subsequent parametric amplification, pulses with more than 0.5 mJ energy were obtained with spectral bandwidth supporting transform-limited pulse durations as short as 23 fs. (C) 2018 Elsevier B.V. All rights reserved.