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arXiv · 2610.22866

Maximizing Smith-Purcell radiation intensity via multi-parameter optimization

Xiaojie Yang·Shichao Zhao·Xinyu Liu·Suguo Chen·Yue Wang·Ping Zhang·Zhigang Lu·Zhanliang Wang·Sunchao Huang·Yubin Gong
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Abstract

Smith Purcell radiation offers a versatile platform for terahertz light matter interactions and compact source development, with intensity enhancement as a key priority. Using particle in cell simulations across a duty cycle range of from 0.1 to 0.9 at 0.4, 0.5, and 0.6 THz, we optimize the grating period, electron kinetic energy and duty cycle. The intensity exhibits a unimodal dependence on the grating period at all three frequencies, with peak enhancements of 96, 34, and 17.5 fold relative to our reference baseline . The optimal duty cycle shifts from 0.2 to 0.4 with increasing frequency, a trend arising from the trade off between coherent superposition and beam-wave coupling under fixed length conditions. These results provide systematic design guidelines for compact tabletop terahertz sources.

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Xiaojie Yang, Shichao Zhao, Xinyu Liu, Suguo Chen, Yue Wang, Ping Zhang, Zhigang Lu, Zhanliang Wang, Sunchao Huang, Yubin Gong. 2026-10-16. Maximizing Smith-Purcell radiation intensity via multi-parameter optimization. https://arxiv.org/abs/2610.22866

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