Single-shot in situ pulse-duration measurement using plasma grating
Abstract
Accurate measurement of the pulse duration of ultrashort, ultra-intense laser pulses at focus is essential for strong-field science. Most existing diagnostics, however, cannot allow direct in situ measurement in the focal region because of damage-threshold limits and unavoidable spatial averaging. We present a direct single-shot far-field diagnostic based on a plasma grating. In this method, the pulse duration is encoded in the axial length of an interference-written plasma grating and retrieved from the corresponding Bragg-diffraction signal. Comparison with near-field (pre-focus) autocorrelator measurements and far-field (at-focus) scanning measurements confirms single-shot pulse-duration retrieval in the focal region over 35-130 fs, and the method remains effective at a peak intensity of . In principle, the measurable range can be extended to 15-300 fs and to higher peak intensities. The method is insensitive to the laser central wavelength and offers a practical approach to far-field diagnostics in high-power laser systems.
Cite
@article{arxiv.2603.10358,
title = {Single-shot in situ pulse-duration measurement using plasma grating},
author = {Jimin Wang and Yanlei Zuo and Kainan Zhou and Zhaoli Li and Pengyu Wei and Xiao Wang and Jie Mu and Xiaodong Wang and Xiaoming Zeng and Zhaohui Wu and Hao Peng and C. Riconda and S. Weber},
journal= {arXiv preprint arXiv:2603.10358},
year = {2026}
}