Spectral phase reconstruction of femtosecond laser pulse from interferometric autocorrelation and evolutionary algorithm

Abstract

We report on the complete temporal characterization of femtosecond laser pulses from second-order interferometric autocorrelation and laser spectrum measurements. The method exploits a newly developed autocorrelator based on a two photon-absorption signal produced directly within a camera sensor so as to provide a single-shot interferometric autocorrelation of great reliability and robustness. Interferometric autocorrelation trace and laser spectrum are exploited for a spectral phase retrieval via an evolutionary algorithm. The quality of the reconstruction for highly modulated spectral phases imprinted by a pulse shaper confirms the reliability of the method. The autocorrelator is compact, robust and easy to use. Possible improvements are discussed.

Neural-network-powered pulse reconstruction from one-dimensional interferometric correlation traces

“…The corresponding cross-correlation trace obtained with this stretched pulse is shown in Figure 1g. As clearly indicated previously [14,21], minimum three measurements are required to retrieve the pulses from 1D datasets (although the pulse retrieval from only two measurements has also been reported [40]), and adding extra information can only lead to a better convergence of an iterative algorithm and a higher level of its reliability. Here, four 1D datasets -spectra of both pulses and two interferometric cross-correlation traces obtained with the glass plate in and out of the interferometer's arm -were used to reconstruct the electric field 𝐸 ?…”