Broadband Spectral Shaping of Regenerative Amplification with Extra-Cavity Waveplate for Cross Polarized Wave Generation

Abstract

We demonstrated extra-cavity gain narrowing pre-compensating in a regenerative amplifier with a multi-order triple-wavelength waveplate (WP). With a 1.117 mm thickness quartz waveplate, which was placed on the stretcher, the gain narrowing effect was reduced efficiently, the output spectral bandwidth was broadened from 25 nm to 40 nm, the broadest spectral pulse was compressed to 33.2 fs and the output energy was 1.5 mJ, the as same as with no waveplate. Then, the amplified pulses were used for cross polarized wave (XPW) generation, and the generated XPW spectra were broadened from 45 nm without WP to 68 nm with WP, with a conversion efficiency of 15%. This simple method can produce broader output spectra with a broader seed beam.

Keywords

• waveplate
• gain narrowing
• regenerative amplification
• cross polarized wave generation