Compression of high-power laser pulse leads to increase of electron acceleration efficiency

TL;DR

This paper demonstrates through 3D PIC simulations that compressing high-power laser pulses enhances electron acceleration efficiency, achieving over 50% conversion rate with Joule-level energies by optimal pulse and plasma matching.

Contribution

It introduces a universal method of pulse compression and plasma matching to maximize high-energy electron yield in laser-plasma interactions.

Findings

Pulse compression to 10 fs increases electron bunch charge.

Conversion efficiency exceeds 50% with Joule-level pulses.

Optimal laser and plasma parameters are identified.

Abstract

Propagation of ultrarelativistically intense laser pulse in a self-trapping mode in a near critical density plasma makes it possible to produce electron bunches of extreme parameters appropriate for different state of art applications. Based on the 3D PIC simulations, it has been demonstrated how the best efficiency of electron acceleration in terms of the total charge of high-energy electrons and laser-to-electrons conversion rate can be achieved. For given laser pulse energy the universal way is a proper matching of laser hot spot size and electron plasma density to the laser pulse duration. The recommendation to achieve the highest yield of high-energy electrons is to compress laser pulse as much as possible. As example, compression of the few tens fs pulse to the 10 fs pulse leads to generation of the high-energy electron bunch with the highest total charge to exhibit conversion efficiency exceeding 50% for the Joule-level laser pulse energies.