Spatiotemporal pulse characterization with far-field beamlet cross-correlation

TL;DR

This paper introduces a simple, effective method for spatiotemporal characterization of ultra-short laser pulses using far-field interferometry and inverse Fourier transform spectroscopy, enabling quick alignment and optimization.

Contribution

It presents a novel, straightforward approach that requires minimal optical components and simple analysis for detailed pulse characterization and optimization.

Findings

Successfully measured 100 TW laser pulse spatiotemporal profile

Validated the method with ray-tracing simulations

Enabled one-shot pulse alignment and PFC suppression

Abstract

We present a novel, straightforward method for spatiotemporal characterization of ultra-short laser pulses. The method employs far-field interferometry and inverse Fourier transform spectroscopy, built on the theoretical basis derived in this paper. It stands out in its simplicity: it requires few non-standard optical elements and simple analysis algorithms. This method was used to measure the space-time intensity of our 100 TW class laser and to test the efficacy of a refractive doublet as a suppressor of pulse front curvature (PFC). The measured low-order spatiotemporal couplings agreed with ray-tracing simulations. In addition, we demonstrate a one-shot measurement technique, derived from our central method, which allows for quick and precise alignment of the compressor by pulse front tilt (PFT) minimization and for optimal refractive doublet positioning for the suppression of PFC.