Quasi-monochromatic bright gamma-ray generation from synchronized Compton scattering via azimuthal spatial-temporal coupling

TL;DR

This paper introduces a novel azimuthal spatial-temporal convertor that enables synchronized Compton scattering, producing quasi-monochromatic gamma rays with high efficiency using high-power lasers.

Contribution

It proposes a new helical parabolic geometry to decouple focal strength from laser spot size, enhancing gamma-ray monochromaticity and yield in laser-plasma interactions.

Findings

Achieves synchronized ICS with nearly identical divergence angles

Resolves the efficiency versus energy spread dilemma

Enables high-power laser gamma-ray generation beyond relativistic fields

Abstract

High energy photons can be generated via inverse Compton scattering (ICS) in the collision between energetic electrons and intense laser pulse. The development of laser plasma accelerators promises compact and all-optical gamma-ray sources by colliding the electrons from laser wakefield accelerators to its high-power driving pulse reflected by a plasma mirror. However, the law of optical focusing hinders realization of both high photon yield and monochromatic spectrum in this scenario. We propose an azimuthal spatial-temporal convertor that decouples the focal field strength from laser spot size using helical parabolic geometry. It decomposes the driving laser beam into a pulse train of almost identical divergence angle and focal depth, creating synchronized ICS in the optimized linear regime. The scheme resolves the dilemma between high efficiency and narrow energy spread, facilitating the generation of monochromatic gamma-ray using high power lasers beyond relativistic field strengths.