High-brilliance ultra-narrow-band x-rays via electron radiation in colliding laser pulses

TL;DR

This paper proposes a compact, high-brilliance x-ray source using relativistic electrons and counter-propagating laser pulses, achieving ultra-narrow bandwidths and tunable spectral features comparable to large-scale facilities.

Contribution

It introduces a novel setup for narrow-band x-ray generation with moderate laser and electron energies, offering a table-top alternative to large-scale XFELs.

Findings

Achieves x-ray bandwidth of about 10^{-4}

Brilliance exceeds state-of-the-art Compton sources by an order of magnitude

Allows tunable single peak or comb-like x-ray spectra

Abstract

A setup of a unique x-ray source is put forward employing a relativistic electron beam interacting with two counter-propagating laser pulses in the nonlinear few-photon regime. In contrast to Compton scattering sources, the envisaged x-ray source exhibits an extremely narrow relative bandwidth of the order of $10^{-4}$, comparable with an x-ray free-electron laser (XFEL). The brilliance of the x-rays can be an order of magnitude higher than that of a state-of-the-art Compton source. By tuning the laser intensities and the electron energy, one can realize either a single peak or a comb-like x-ray source of around keV energy. The laser intensity and the electron energy in the suggested setup are rather moderate, rendering this scheme compact and table-top size, as opposed to XFEL and synchrotron infrastructures.