0.42 TW 2-cycle pulses at 1.8 $\mu$m via hollow-core fiber compression
Résumé
By employing pulse compression with a stretched hollow-core fiber, we generated 2-cycle pulses at
1.8 $\mu$m (12 fs) carrying 5 mJ of pulse energy at 100 Hz repetition rate. This energy scaling in the
mid-infrared spectral range was achieved by lowering the intensity in a loose focusing condition,
thus suppressing the ionization induced losses. The correspondingly large focus was coupled into a
hollow-core fiber of 1 mm inner diameter, operated with a pressure gradient to further reduce detrimental
nonlinear effects. The required amount of self-phase modulation for spectral broadening
was obtained over 3 m of propagation distance