We demonstrate an alternative concept of laser wavelength conversion to the NIR – SWIR range with simultaneous multiple spectral broadening based on transient stimulated Raman chirped pulse amplification (TSRCPA) and pulse compression to fs pulsewidth for the sub-TW class lasers, with possible application in the next generation LIDARs. Transform limited pulses of a Yb:YAG laser with a duration of ~1.2 ps were used to pump a multistage TSRCPA based on KGW crystals seeded with 1100 – 2500 nm supercontinuum. A 16-times spectral broadening was shown after TSRCPA compared to pump pulses, conversion efficiency 55%, and compression to ~145 fs. This concept, extended for gases and diamond with larger Stokes shifts, allows further exploration of SWIR range, especially for the 2nd Stokes.
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