X-ray pulse generation with ultra-fast flipping of its orbital angular momentum

TL;DR

This paper proposes a simulation-based method to generate tunable, attosecond pulse trains of X-ray light with orbital angular momentum, featuring rapid flipping of OAM handedness without external optics.

Contribution

It introduces a novel technique for temporally tailoring X-ray OAM radiation, enabling control over pulse timing and OAM handedness in simulations.

Findings

Generation of attosecond OAM pulse trains demonstrated in simulations

Method allows for tunable wavelength and OAM handedness modulation

No external optics required for OAM pulse shaping

Abstract

A method to temporally tailor the properties of X-ray radiation carrying Orbital Angular Momentum (OAM) is presented. In simulations, an electron beam is prepared with a temporally modulated micro-bunching structure which, when radiating at the second harmonic in a helical undulator, generates OAM light with a corresponding temporally modulated intensity. This method is shown to generate attosecond pulse trains of OAM light without the need for any additional external optics, making the wavelength range tunable. In addition to the OAM pulse train, the method can be adapted to generate radiation where the handedness of the OAM mode may also be temporally modulated (flipped).