Single-shot spatiotemporal characterization of ultrashort lasers based on spectral interferometry with fiber array

Abstract In the realm of ultra-intense laser physics, the precise characterization of laser pulses is indispensable for ensuring optimal peak power and experimental fidelity. However, accurate measurement of spatiotemporal coupling parameters remains a significant challenge, particularly for petawatt laser facilities that predominantly operate at low repetition rates or in single-shot mode. Here, we present a method named spectral interferometry with fiber array for single-shot spatiotemporal characterization (SIFAST), which utilizes a specially designed single-mode fiber array combined with spectral interferometry to eliminate the dimensional limitations of standard cameras. We demonstrate that SIFAST successfully characterizes various vortex beams and complex spatiotemporal couplings, allowing for the reconstruction of the complete three-dimensional spatiotemporal structure of a laser pulse in a single shot. This linear measurement approach makes full characterization and subsequent optimization of ultra-intense laser pulses feasible, paving the way for higher-precision experiments in high-field physics.