Repetitive petawatt-class laser with near-diffraction-limited focal spot and transform-limited pulse duration

Abstract

A repetitive petawatt-class Ti:sapphire laser system operating with high spatial and temporal beam quality is demonstrated. Maximum pulse energy of 30 J is obtained via five multi-pass amplification stages. Closed-loop feedback control systems in the temporal and spatial domains are used to yield Fourier-transform-limited pulse duration (33.7 fs), and diffraction-limited focal spot sizes (with several different tight focusing optics). The laser parameters have been fully characterized at high-power, and are monitored in real-time, to ensure that they meet the experimental requirements for laser-wakefield electron acceleration and x-ray generation.