Time-domain ptychography of over-octave-spanning laser pulses in the single-cycle regime.

We report, to the best of our knowledge, the first application of time-domain ptychography for the characterization of few-cycle laser pulses. Our method enables zero-additional phase measurements of over-octave-spanning laser pulses in the single cycle regime. The spectral phase is recovered using a robust ptychography algorithm that requires no input apart from the measured data trace. In addition to numerical tests, we validate our new device experimentally by reconstructing the complex electric field of a 1.5 cycle laser pulse with a bandwidth spanning 490 to 1060 nm. We further check the accuracy of our device by comparing the measured phases of octave-spanning chirped pulses to the known dispersion of fused silica glass.

Self-referenced characterization of space-time couplings in near-single-cycle laser pulses.

We report on the characterization of space-time couplings in high-energy sub-2-cycle 770 nm laser pulses using a self-referencing single-frame method. Using spatially encoded arrangement filter-based spectral phase interferometry for direct electric field reconstruction, we characterize few-cycle pulses with a wavefront rotation of 2.8×1011 rev/s (1.38 mrad per half-cycle) and pulses with pulse front tilts ranging from -0.33 fs/µm to -3.03 fs/µm in the focus.