Pulse compression of white-light continuum generated at 1053 nm in bulk sapphire: an experimental study

Abstract

The white-light continuum in optical bulk material has the potential to be used as a seed pulse in optical parametric amplifiers, which entails the compression of seed pulses to temporally overlap with pump pulses. An experimental study of the compression of the white-light continuum is reported in this article. Both chirped mirror compression and prism pair compression methods are used. The 280 fs pulses centered at 1053 nm are employed to generate a white-light continuum in a bulk sapphire plate; the spectrum of a white-light continuum spans from 650 nm to 1000 nm and its second harmonic generation (SHG) is measured. The scanning SHG frequency resolved optical gating technique was used to characterize the compression of the white-light continuum. Prism pair only compression of the (650–1000) nm spectra yielded 190 fs, with chirp mirrors added after leading to 150 fs. Spectral masking of the spectrum below 850 nm inside the prism compressor resulted in a pulse duration of ~120 fs for the 850–1000 nm spectral portion of the pulses.