English

100% Reliable Frequency-Resolved Optical Gating Pulse-Retrieval Algorithmic Approach

Signal Processing 2019-10-02 v2 Optics

Abstract

Frequency-resolved optical gating (FROG) is widely used to measure ultrashort laser pulses, also providing an excellent indication of pulse-shape instabilities by disagreement between measured and retrieved FROG traces. FROG, however, requires -- but currently lacks -- an extremely reliable pulse-retrieval algorithm. So, this work provides one. It uses a simple procedure for directly retrieving the precise pulse spectrum from the measured trace. Additionally, it implements a multi-grid scheme, also quickly yielding a vastly improved guess for the spectral phase before implementing the entire measured trace. As a result, it achieves 100% convergence for the three most common variants of FROG for pulses with time-bandwidth products as high as 100, even with traces contaminated with noise. Here we consider the polarization-gate (PG) and transient-grating (TG) variants of FROG, which measure amplified, UV, and broadly tunable pulses. Convergence occurs for all of the >20,000 simulated noisy PG/TG FROG traces considered and is also faster.

Keywords

Cite

@article{arxiv.1811.11100,
  title  = {100% Reliable Frequency-Resolved Optical Gating Pulse-Retrieval Algorithmic Approach},
  author = {Rana Jafari and Rick Trebino},
  journal= {arXiv preprint arXiv:1811.11100},
  year   = {2019}
}
R2 v1 2026-06-23T06:22:19.753Z