A Survey of Spatio-Temporal Couplings throughout High-Power Ultrashort Lasers

TL;DR

This survey explores spatio-temporal couplings in high-power ultrashort lasers, presenting novel measurements at different stages of CPA systems to improve understanding and optimization of these complex laser sources.

Contribution

It provides the first comprehensive measurement of STCs at various points in high-power CPA laser systems, highlighting sources and encouraging broader characterization.

Findings

Identification of diverse spatio-temporal effects

Measurement of STCs at multiple laser stages

Implications for laser optimization and understanding

Abstract

The investigation of spatio-temporal couplings (STCs) of broadband light beams is becoming a key topic for the optimization as well as applications of ultrashort laser systems. This calls for accurate measurements of STCs. Yet, it is only recently that such complete spatio-temporal or spatio-spectral characterization has become possible, and it has so far mostly been implemented at the output of the laser systems, where experiments take place. In this survey, we present for the first time STC measurements at different stages of a collection of high-power ultrashort laser systems, all based on the chirped-pulse amplification (CPA) technique, but with very different output characteristics. This measurement campaign reveals spatio-temporal effects with various sources, and motivates the expanded use of STC characterization throughout CPA laser chains, as well as in a wider range of types of ultrafast laser systems. In this way knowledge will be gained not only about potential defects, but also about the fundamental dynamics and operating regimes of advanced ultrashort laser systems.