Frequency-resolved optical gating of highly chirped ultrabroadband pulses

TL;DR

This paper introduces a simplified and efficient FROG reconstruction algorithm for highly chirped ultrabroadband pulses, reducing data size and convergence time while maintaining accuracy, verified through simulations and experiments.

Contribution

A new FROG reconstruction method using stationary phase approximation for highly chirped pulses, improving speed and data efficiency over traditional Fourier-based approaches.

Findings

The method accurately reconstructs highly chirped pulses.

Significant reduction in data size and convergence time.

Validated through simulations and experimental measurements.

Abstract

This article describes a simplified reconstruction algorithm for frequency resolved optical gating (FROG) measurements of highly (monotonically) chirped pulses. The FROG traces are calculated using the stationary phase approximation, significantly reducing the data size and convergence time compared to discrete Fourier transform based methods. The method is verified via second harmonic generation FROG simulations and measurements of pulses centred at 800nm with a bandwidth of 55nm stretched to 32ps at the 1% intensity level, corresponding to a time-bandwidth product of 830.