Real-time pulse length measurement of few-cycle laser pulses using above-threshold ionization.

The pulse lengths of intense few-cycle (4-10 fs) laser pulses at 790 nm are determined in real-time using a stereographic above-threshold ionization (ATI) measurement of Xe, i.e. the same apparatus recently shown to provide a precise, real-time, every-single-shot, carrier-envelope phase measurement of ultrashort laser pulses.

Self-compression by femtosecond pulse filamentation: experiments versus numerical simulations.

We analyze pulse self-compression in femtosecond filaments, both experimentally and numerically. We experimentally demonstrate the compression of 45 fs pulses down to a duration of 7.4 fs at millijoule pulse energies.

C60 in intense short pulse laser fields down to 9 fs: excitation on time scales below e-e and e-phonon coupling.

The interaction of C60 fullerenes with 765-797 nm laser pulses as short as 9 fs at intensities of up to 3.7 x 10(14) W cm(-2) is investigated with photoion spectroscopy. The excitation time thus addressed lies well below the characteristic time scales for electron-electron and electron-phonon couplings.

Sub-10 fs pulse characterization using spatially encoded arrangement for spectral phase interferometry for direct electric field reconstruction.

We demonstrate an extremely accurate method for measuring ultrabroadband, sub-10 fs pulses even if they exhibit a highly modulated spectrum, space-time coupling, or both. The method uses a spatially encoded arrangement for spectral phase interferometry for direct electric field reconstruction, which allows a zero additional phase measurement to be performed with a relatively low signal-to-noise ratio in real time and single shot.

Self-compression of millijoule pulses to 7.8 fs duration in a white-light filament.

We demonstrate a novel technique for pulse compression of few-millijoule pulses with shorter than 10 fs duration. Our technique relies on spectral broadening in a white-light filament generated in a noble gas. In this filament we observe self-compression of 45 fs pulses down to below 8 fs duration without the need for any additional dispersion compensation.

Interferometric frequency-resolved optical gating.

We demonstrate a novel variant of frequency-resolved optical gating (FROG) that is based on spectrally resolving a collinear interferometric autocorrelation rather than a noncollinear one. From the interferometric FROG trace, one can extract two terms, the standard SHG-FROG trace and a new phase-sensitive modulational component, which both allow for independent retrieval of the pulse shape. We compare the results of both methods and a separate SPIDER measurement using 6.

High dynamic range characterization of ultrabroadband white-light continuum pulses.

We demonstrate an improved method for characterizing ultrashort pulses. Our apparatus is based on spectral phase interferometry for direct electric-field reconstruction (SPIDER) and particularly suited for measurement of compressed white-light continuum pulses with their strong spectral amplitude variations. Phase-sensitive noise rejection allows for a significant increase of the dynamic range of the SPIDER trace.