Related Experiment Video
Updated: Jun 5, 2026

Low-cost Custom Fabrication and Mode-locked Operation of an All-normal-dispersion Femtosecond Fiber Laser for Multiphoton Microscopy
Published on: November 22, 2019
Complete temporal characterization of asymmetric pulse compression in a laser wakefield
J Schreiber1, C Bellei, S P D Mangles
1Blackett Laboratory, Imperial College, London SW7 2AZ, United Kingdom. j.schreiber@imperial.ac.uk
Abstract:
We present complete experimental characterization of the temporal shape of an intense ultrashort 200-TW laser pulse driving a laser wakefield. The phase of the pulse was uniquely measured by using (second-order) frequency-resolved optical gating. The pulses are asymmetrically compressed and exhibit a positive chirp consistent with the expected asymmetric self-phase-modulation due to photon acceleration or deceleration in a relativistic plasma wave. The measured pulse duration decreases linearly with increasing length and density of the plasma, in quantitative agreement with the intensity-dependent group velocity variation in the plasma wave.

