Arbitrary-Velocity Volkov Wavepackets

TL;DR

This paper demonstrates how to construct Volkov wavepackets with arbitrary velocities by imposing specific momentum correlations, independent of the electromagnetic field parameters.

Contribution

It introduces a method to generate structured wavepackets with customizable velocities, revealing new control over charged particle dynamics in electromagnetic fields.

Findings

Arbitrary velocities can be achieved in Volkov wavepackets.

Momentum correlations influence the wavepacket's trajectory.

The method provides measurable signatures of the tailored velocities.

Abstract

The evolution of a charged lepton in the field of an electromagnetic plane wave can be described as a superposition of Volkov states. Here we demonstrate that imposing specific momentum correlations among Volkov states produces a spatiotemporally structured wavepacket whose probability-density peak travels at an arbitrary, tailored velocity. This velocity can be chosen independently of both the field amplitude and the velocity expectation value. The imposed momentum correlations modify the expectation-value trajectory, providing a measurable signature of the arbitrary velocity within a physical observable.