Extracavity compression technique for high-energy femtosecond pulses

Abstract

We introduce a new extracavity pulse-compression technique suitable for generating high-energy femtosecond pulses. This technique is based on spectral broadening by self-phase modulation in bulk media followed by far-field spatial filtering, which provides a uniform spectral broadening over the spatial profile combined with a transmission of 50%. In principle, this technique allows compression of pulses with energy up to ∼100 mJ by a factor of 3–5. In a proof-of-principle experiment, we compressed a 42-fs, 480-μJ pulse to a 14-fs, 220-μJ pulse.