Two-photon emission from uniform acceleration: Unruh excitation, radiative decay, and field entanglement

TL;DR

This paper investigates two-photon emission from a uniformly accelerated detector, revealing how acceleration influences entanglement and thermal properties of emitted radiation, with implications for quantum field theory in non-inertial frames.

Contribution

It provides an exact quantum state analysis of photon pairs emitted by an accelerated detector, classifying emissions into different modes and exploring entanglement across Rindler wedges.

Findings

Photon pairs are classified into RR, LL, RL, LR modes.

Acceleration induces entanglement and thermal features in emitted radiation.

Emission process involves Unruh excitation and decay mechanisms.

Abstract

We analyze the two-photon emission process of a uniformly accelerated Unruh-DeWitt detector interacting with a massless scalar field in Minkowski spacetime. Using second-order perturbation theory, we derive the exact final quantum state of the field and classify the emitted photon pairs according to their directional decomposition into Unruh modes: right-right (RR), left-left (LL), and mixed (RL/LR) channels. The RR and LL contributions produce photon pairs within a single Rindler wedge, while RL and LR emissions generate entanglement across wedges. The first emission arises from a counter-rotating (Unruh) excitation, followed by a rotating Wigner-Weisskopf-like decay. Our results reveal how acceleration imprints entanglement and thermal structure on the radiation, offering new insight into quantum field theory in non-inertial frames and potential applications in relativistic quantum information.