Relativistic single-electron wavepacket in quantum electromagnetic fields II: Quantum radiation emitted by a uniformly accelerated electron

TL;DR

This paper calculates quantum radiation from relativistic electron wavepackets, revealing that uniform acceleration leads to secular growth in emitted power, with classical interpretation and implications for detecting the Unruh effect.

Contribution

It demonstrates the importance of cubic terms in electrodynamics for quantum radiation and analyzes the behavior of radiation from accelerated electrons, including classical interpretation.

Findings

Quantum radiation from a stationary electron wavepacket vanishes.

Accelerated electrons exhibit secular growth in radiated power over time.

Quantum corrections in blind spots are dominated by transverse deviation correlators.

Abstract

We compute the quantum radiation emitted by wavepackets of relativistic single electrons, both at rest and undergoing uniform acceleration in the Minkowski vacuum of the electromagnetic field. We find that the cubic terms in the original nonlinear action of electrodynamics should be considered in obtaining the quantum radiation to the leading order. We show that the quantum radiation from a single-electron wavepacket at rest vanishes exactly. For a uniformly accelerated electron, the quantum radiated power has secular growth in the long-time regime. We demonstrate that this secular growth has a classical interpretation, and argue that the resummed quantum radiation at late times would not diverge. Regarding experimental proposals for the detection of the Unruh effect from the quantum radiation in the `blind spots' of classical radiation we ascertain that quantum corrections in the two blind spots are fully contributed by the transverse deviation correlators, where the dominant contributions are irrelevant to the Unruh effect in electron microscopes.