# Polarized electron-beam acceleration driven by vortex laser pulses

## TL;DR

This paper introduces a novel all-optical method using vortex laser pulses to generate highly polarized relativistic electron beams, overcoming previous depolarization issues and significantly increasing beam flux.

## Contribution

The study demonstrates, through simulations, that vortex Laguerre-Gaussian laser pulses can effectively produce polarized electron beams with high flux, a breakthrough over traditional Gaussian beam methods.

## Key findings

- Electron spin polarization preserved over 80% in simulations.
- Method enables more than tenfold increase in peak flux of polarized electrons.
- Vortex laser-driven wakefield acceleration overcomes depolarization challenges.

## Abstract

We propose a new approach based on an all-optical set-up for generating relativistic polarized electron beams via vortex Laguerre-Gaussian (LG) laser-driven wakefield acceleration. Using a pre-polarized gas target, we find that the topology of the vortex wakefield resolves the depolarization issue of the injected electrons. In full three-dimensional particle-in-cell simulations, incorporating the spin dynamics via the Thomas-Bargmann Michel Telegdi equation, the LG laser preserves the electron spin polarization by more than 80% at high beam charge and flux. The method releases the limit on beam flux for polarized electron acceleration and promises more than an order of magnitude boost in peak flux, as compared to Gaussian beams. These results suggest a promising table-top method to produce energetic polarized electron beams.

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Source: https://tomesphere.com/paper/1904.03431