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

TL;DR

This paper introduces a simple method to generate intense, tunable x-ray vortex beams in high-gain free-electron lasers by adjusting the wavefront tilt, enabling high-quality vortex amplification without wavelength constraints.

Contribution

The authors present a novel wavefront shaping technique for FELs that produces intense, tunable x-ray vortices with no wavelength limitations and easy implementation.

Findings

Effective vortex generation in high-gain FELs demonstrated.

Method allows tunable wavelength and high-quality vortex beams.

No wavelength restrictions compared to existing methods.

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.