Abstract

In the few-cycle regime, the light-matter interaction becomes extremely sensitive to the pulse shape and it is highly advantageous to use techniques such as frequency resolved optical gating (FROG) and spectral phase interferometry for direct electric field reconstruction (SPIDER) to obtain a full amplitude and phase characterization of the pulse. A unique advantage of SPIDER is a direct and rapid algebraic field reconstruction that makes it well-suited for online monitoring and optimization of the pulse. High intensity few-cycle pulses are typically generated by nonlinear spectral broadening in a gas-filled hollow core fiber (HCF) or a filament followed by compression using chirped mirrors. Using HCFs, pulse energies up to 5 mJ and pulse durations below 4 fs [1] have been previously demonstrated. Both these methods can lead to pulses with spatially-dependent temporal properties, but to-date, only a few spatially resolved pulse characterization measurements have been made and only for many-cycle pulses [2, 3].

© 2011 Optical Society of America