Weak-Strong Steady-State Microbunching Accelerator Light Source

Xiujie Deng; Alexander Wu Chao; Wenhui Huang; Zhilong Pan; Chuanxiang Tang; Jingyuan Zhao

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arXiv · 2607.09243

Weak-Strong Steady-State Microbunching Accelerator Light Source

Xiujie Deng·Alexander Wu Chao·Wenhui Huang·Zhilong Pan·Chuanxiang Tang·Jingyuan Zhao

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Abstract

We propose a phase space manipulation involving one energy modulation sandwiched by two dispersion sections which converts a bunched particle beam or bunch train to ultra-high-harmonic density modulation, while the energy modulation in principle can be arbitrarily weak. The same scheme can also be used for energy bunching, creating energy levels in a bunched beam. We further propose a mechanism invoking three laser modulators in a storage ring to longitudinally focus the electron beam both weakly and strongly, such that a microbunch train and its high-density-harmonics or energy bunching form and sustain turn-by-turn. We call this mechanism weak-strong steady-state microbunching (Weak-Strong SSMB). The longitudinal beta function can vary by seven orders of magnitude along such a ring, with the minimal value squeezed to 10 nm. An example application of Weak-Strong SSMB for kW coherent EUV radiation is presented. Extension to X-ray can be anticipated. An energy-leveled electron beam enables $\gamma$-ray frequency comb production. The ideas can be scaled to wavelengths like RF and THz, for bunch length and energy spread control, ultrashort X-ray and coherent THz generation. Our work establishes a new paradigm for longitudinal dynamics study, accelerator light source development, and opens great potential for accelerator physics and technology.

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Xiujie Deng, Alexander Wu Chao, Wenhui Huang, Zhilong Pan, Chuanxiang Tang, Jingyuan Zhao. 2026-07-10. Weak-Strong Steady-State Microbunching Accelerator Light Source. https://arxiv.org/abs/2607.09243

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