Amplitude and chirp characterization of high-power laser pulses in the 5-fs regime.

Frequency-resolved optical gating (FROG) based on second-harmonic generation has been demonstrated to be capable of high-fidelity measurement of the electric-field envelope and of the temporal evolution of the instantaneous carrier frequency of 0.1-TW 5-fs pulses without the need for any correction for systematic experimental errors. At a 1-kHz repetition rate, pulse energies of a few microjoules are sufficient for reliable FROG characterization of pulses with durations down to the single-cycle regime. The results obtained reveal that carefully designed hollow-fiber chirped-mirror compressors are able to deliver high-power sub-10-fs pulses with a smooth Gaussianlike leading edge that has an intensity contrast of approximately 10(-2) .

Compression of high-energy laser pulses below 5 fs.

High-energy 20-fs pulses generated by a Ti:sapphire laser system were spectrally broadened to more than 250 nm by self-phase modulation in a hollow fiber filled with noble gases and subsequently compressed in a broadband high-throughput dispersive system. Pulses as short as 4.5 fs with energy up to 20-microJ were obtained with krypton, while pulses as short as 5 fs with energy up to 70 microJ were obtained with argon. These pulses are, to our knowledge, the shortest generated to date at multigigawatt peak powers.

Generation of 0.1-TW 5-fs optical pulses at a 1-kHz repetition rate.

A compact all-solid-state femtosecond Ti:sapphire oscillator¿amplifier system using no grating-based pulse stretcher produces 20-fs, 1.5-mJ pulses at a 1-kHz repetition rate. The pulses are subsequently compressed in a hollow-fiber chirped-mirror compressor. The system delivers bandwidth-limited 5-fs, 0.5-mJ pulses at 780 nm in a diffraction-limited beam.