Simultaneous measurement of the absolute and relative time delay of a tiled-aperture coherent beam combination via the double-humped spectral beam interferometry

• Published in: Optics express Vol. 28; no. 24; pp. 35498 - 35505
• Main Authors: Liu, Keyang, Song, Liwei, Liu, Yanqi, Wang, Xinliang, Huang, Zhiyuan, Tang, Yunhai, Wang, Xiaobin, Liu, Zhengzheng, Leng, Yuxin
• Format: Journal Article
• Language: English
• Published: United States 23.11.2020
• ISSN: 1094-4087; 1094-4087
• DOI: 10.1364/OE.405430

Coherent beam combination (CBC) is a promising technology for achieving several hundred petawatts and even EW-level lasers. However, the measurement of the synchronization error and the time jitter of CBC is one of key technical issues, especially in the few-cycle PW-level laser facilities. In this paper, we demonstrate that the absolute time delay (ATD) and the relative time delay (RTD) for a tiled-aperture CBC can simultaneously be measured by using the double-humped spectral beam interferometry. The experimental study also was demonstrated. A root-mean-square deviation of approximately λ/38 (70 as) and a combining efficiency of 87.3% at 1 Hz closed feedback loop was obtained, respectively. Due to the wide adjustment range and a vast resisting beam energy disturbance capacity, this technique provide an effective and practical solution for measuring simultaneously the ATD and the RTD in the few-cycle PW-level laser pulses CBC.