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arXiv · 2409.16542

Intense X-ray Vortices Generation via Wavefront Shaping in high-gain Free-Electron Lasers

Zhikai Zhou·Yin Kang·Weishi Wan·Chao Feng
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Abstract

The x-ray vortex optical beam, distinguished by its topological charge and orbital angular momentum, offers new insights in probing complex electronic structures, enhancing material characterization, and advancing high-resolution imaging techniques. Here we propose a straightforward and effective method to generate intense x-ray vortices with tunable wavelengths in high-gain free-electron lasers (FELs). By simply adjusting the wavefront tilt of the radiation pulse during the FEL gain process, high-quality vortex beam can be amplified until saturation. Compared to existing methods for FEL vortex generation, the proposed technique imposes no wavelength limitations and can be easily implemented in high-gain FEL facilities, regardless of the operation modes.

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Zhikai Zhou, Yin Kang, Weishi Wan, Chao Feng. 2024-09-25. Intense X-ray Vortices Generation via Wavefront Shaping in high-gain Free-Electron Lasers. https://doi.org/10.1103/physrevlett.134.205001

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