Photo-Emission of a Single-Electron Wave-Packet in a Strong Laser Field

TL;DR

This paper investigates the radiation emitted by a single-electron wave packet in a strong laser field, establishing a quantum-classical relation and demonstrating the wave packet's point-like emission behavior despite spreading.

Contribution

It introduces a quantum framework linking electron wave packets and classical emission, showing wave packets act as point emitters regardless of spreading.

Findings

Wave packet behaves as a point-like emitter.

Quantum and classical formulations are related via the Wigner function.

Experimental setup proposed to test the wave packet emission behavior.

Abstract

The radiation emitted by a single-electron wave packet in an intense laser field is considered. A relation between the exact quantum formulation and its classical counterpart is established via the electron's Wigner function. In particular we show that the wave packet, even when it spreads to the scale of the wavelength of the driving laser field, cannot be treated as an extended classical charge distribution but rather behaves as a point-like emitter carrying information on its initial quantum state. We outline an experimental setup dedicated to put this conclusion to the test.