Using a Bessel light beam as an ultra-short period helical undulator

TL;DR

This paper proposes using a Bessel light beam with orbital angular momentum as an ultra-short period undulator to generate synchrotron radiation, potentially reducing electron energy requirements for X-ray production.

Contribution

It introduces a novel laser-based undulator utilizing Bessel beams, enabling sub-millimeter period lengths for enhanced X-ray generation.

Findings

The Bessel beam induces a transverse force on electrons, acting as an undulator.

The period length of this undulator can reach sub-millimeter levels.

This approach could significantly lower the electron energy needed for X-ray production.

Abstract

The undulator is a critical component to produce synchrotron radiation and free electron laser. When a Bessel light beam carrying the orbit angular momentum co-propagates with an electron beam, a net transverse deflection force will be subjected to the electron beam. As a result of dephasing effect, the deflection force will oscillate acting as an undulator. For such a laser based undulator, the period length can reach sub-millimeter level, which will greatly reduce the electron energy for the required X-ray production.