Third-order correlator for measuring the time profile of petawatt laser pulses

A third-order correlator with a single-shot time window and a full dynamic range of 108 is developed. The time contrast of radiation from the front-end system of a petawatt femtosecond laser complex measured with the correlator within time windows ±1 ps and ±100 ps was 104 and more than 108, respectively. Based on the theoretical analysis of the cross-correlator operation, a number of requirements providing the optimal functioning of the cross-correlator are found. The reasons restricting the technical parameters of the correlator are discussed.