Measuring the temporal contrast on the petawatt PETAL laser facility using a third-order cross-correlator diagnostic with 40 ps temporal range

In this paper, we present the architecture of a 40 ps, 107 dynamic range single-shot third-order cross-correlator for temporal contrast measurement of low repetition rate ultra-high intensity facilities. The cross-correlator employs a concatenation process to generate the complete 300 ps temporal contrast profile, using a limited number of shots. The shot-to-shot fluctuations in energy and pulse duration are deconvoluted. Simulations of the diagnostic's achievable performance have been conducted, and an experimental demonstration is presented. The impact of phase and amplitude spectral defects on the diagnostic's performance resolution will be discussed. To illustrate this point, a complete curve of the PETAL temporal contrast is obtained and discussed.