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  • Open Access

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

Arash Azizi*

  • The Institute for Quantum Science and Engineering, Texas A&M University, College Station, Texas 77843, USA

  • *Contact author: sazizi@tamu.edu
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Phys. Rev. D 112, 045008 – Published 20 August, 2025

DOI: https://doi.org/10.1103/bck9-x7gt

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 counterrotating (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 noninertial frames and potential applications in relativistic quantum information.

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Phys. Rev. D 112, 045008– Published 20 August, 2025
  • Received 21 May 2025
  • Accepted 31 July 2025
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Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article’s title, journal citation, and DOI. Funded by SCOAP3.

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