Maximizing energy deposition by shaping few-cycle laser pulses

TL;DR

This study demonstrates that shaping few-cycle laser pulses with specific temporal profiles enhances energy deposition in gas plasmas, leading to stronger shockwaves and luminescence by optimizing ionization timing.

Contribution

It provides experimental evidence that pulse shape tailoring can significantly improve energy transfer efficiency in laser-induced plasma processes.

Findings

Fast-rising triangular pulses induce earlier ionization.

Shaped pulses produce stronger shockwaves and plasma luminescence.

Earlier free electron availability enhances inverse Bremsstrahlung absorption.

Abstract

We experimentally investigate the impact of pulse shape on the dynamics of laser-generated plasma in rare gases. Fast-rising triangular pulses with a slower decay lead to early ionization of the air and depose energy more efficiently than their temporally reversed counterparts. As a result, in both argon and krypton, the induced shockwave as well as the plasma luminescence are stronger. This is due to an earlier availability of free electrons to undergo inverse Bremsstrahlung on the pulse trailing edge. Our results illustrate the ability of adequately tailored pulse shapes to optimize the energy deposition in gas plasmas.