Enhanced quantum radiation with flying-focus laser pulses

TL;DR

This paper demonstrates that using flying-focus laser pulses, which co-propagate with electrons, significantly enhances quantum radiation emission and energy loss compared to traditional stationary-focus pulses, due to more favorable scaling with interaction time.

Contribution

The study introduces the concept of flying-focus laser pulses for electron interactions, showing they outperform stationary-focus pulses in quantum radiation processes.

Findings

Flying-focus pulses increase photon yield compared to stationary-focus pulses.

Energy loss scales more favorably with interaction time in flying-focus configuration.

Monte Carlo simulations confirm the advantages of flying-focus over stationary-focus pulses.

Abstract

The emission of a photon by an electron in an intense laser field is one of the most fundamental processes in electrodynamics and underlies the many applications that utilize high-energy photon beams. This process is typically studied for electrons colliding head-on with a stationary-focus laser pulse. Here, we show that the energy lost by electrons in the quantum regime and the yield of emitted photons can be substantially increased by replacing a stationary-focus pulse with an equal-energy flying-focus pulse whose focus co-propagates with the electrons. These advantages of the flying focus result from the energy loss and the photon yield scaling more favorably with the interaction time than the laser intensity in the quantum regime, with the latter also holding in the classical regime. Monte Carlo simulations of electrons colliding with equal-energy stationary and flying-focus laser pulses demonstrate these advantages.