Poor man's source for sub 7 fs: a simple route to ultrashort laser pulses and their full characterization

A practicable and economic method for the generation and full characterization of laser pulses ranging down to sub 7 fs duration with energies spanning the full microJ domain is presented. The method utilizes a self-induced and self-guiding filamentation of titanium-sapphire based, amplified pulses in air for spectral broadening, a standard chirp mirror compression scheme and transient grating frequency resolved optical gating for determining the spectral phase over the full visible to near infrared range. In this manner, few-cycle laser pulses with a high quality in the spatial beam profile have been generated in an robust arrangement with a minimal amount of standard optical components for their full characterization. The optical scheme demonstrates an uncomplicated, versatile access to this regime of pulsed laser radiation accompanied by a comprehensive analysis.