Laser-intensity-spike-dominated hot electron generation from two-plasmon decay instability driven by moderate-bandwidth pulses

C. Yao; Z. H. Cai; X. Wang; X. C. Wang; H. R. Yin; Z. A. Zhu; C. W. Lian; Y. Ji; X. Jiang; S. M. Xu; Y. Y. Yao; L. Y. Yang; J. N. Zhang; D. Meng; T. Peng; H. Wen; C. Z. Xiao; K. Y. Meng; J. Li; R. Yan; P. Yuan; Z. Zhang; L. Hao; Q. Jia; W. Feng; H. H. An; H. Y. Liu; Z. Y. Xie; P. P. Wang; C. Wang; A. Lei; X. H. Zhao; Z. H. Fang; W. Wang; Y. Q. Gu; Y-K. Ding; J. Zheng

arXiv · 2606.26054

Laser-intensity-spike-dominated hot electron generation from two-plasmon decay instability driven by moderate-bandwidth pulses

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Abstract

Our direct-drive-relevant experiments on the low-coherence Kunwu laser facility identify two-plasmon decay (TPD) as the primary source of hot electrons, and demonstrate for the first time that broadband laser pulses enhance TPD. Using particle-in-cell simulations, we attribute this TPD enhancement and the consequent hot electron production to stochastic intensity spikes inherent in broadband laser fields, robust in both weakly- and strongly-driven regimes. These findings suggest that mitigating hot electron generation requires suppressing these intensity spikes.

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C. Yao, Z. H. Cai, X. Wang, X. C. Wang, H. R. Yin, Z. A. Zhu, C. W. Lian, Y. Ji, X. Jiang, S. M. Xu, Y. Y. Yao, L. Y. Yang, J. N. Zhang, D. Meng, T. Peng, H. Wen, C. Z. Xiao, K. Y. Meng, J. Li, R. Yan, P. Yuan, Z. Zhang, L. Hao, Q. Jia, W. Feng, H. H. An, H. Y. Liu, Z. Y. Xie, P. P. Wang, C. Wang, A. Lei, X. H. Zhao, Z. H. Fang, W. Wang, Y. Q. Gu, Y-K. Ding, J. Zheng. 2026-06-24. Laser-intensity-spike-dominated hot electron generation from two-plasmon decay instability driven by moderate-bandwidth pulses. https://arxiv.org/abs/2606.26054

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