Sub-laser-cycle control of relativistic plasma mirrors

TL;DR

This paper demonstrates how sub-cycle laser waveform shaping enables precise control over high-order harmonic generation and relativistic electron emission from plasma mirrors, advancing ultrafast plasma physics.

Contribution

It introduces a method to control plasma mirror emissions using temporally-shaped laser fields, combining experimental measurements with advanced simulations.

Findings

Phase delay influences harmonic and electron emission properties.

Sub-cycle laser shaping allows fine control of relativistic electron bunches.

Experimental results align with Particle-In-Cell simulation predictions.

Abstract

We present measurements of high-order harmonics and relativistic electrons emitted into the vacuum from a plasma mirror driven by temporally-shaped ultra-intense laser waveforms, produced by collinearly combining the main laser field with its second harmonic. We experimentally show how these observables are influenced by the phase delay between these two frequencies at the attosecond timescale, and relate these observations to the underlying physics through an advanced analysis of 1D/2D Particle-In-Cell simulations. These results demonstrate that sub-cycle shaping of the driving laser field provides fine control on the properties of the relativistic electron bunches responsible for harmonic and particle emission from plasma mirrors.