QED with a parabolic mirror

TL;DR

This paper studies how a parabolic mirror affects quantum electrodynamics of a two-level atom, analyzing spontaneous emission modifications and single-photon states, with implications for efficient atom-photon interactions.

Contribution

It provides a detailed analysis of atom-photon interactions in a parabolic cavity, including spontaneous emission modifications and photon state characterization, using semiclassical methods.

Findings

Spontaneous emission is modified by the parabolic boundary in the optical regime.

The asymptotic single-photon state can efficiently excite the atom.

Photon-path representation approximates transition amplitudes effectively.

Abstract

We investigate the quantum electrodynamics of a single two-level atom located at the focus of a parabolic cavity. We first work out the modifications of the spontaneous emission induced by the presence of this boundary in the optical regime, where the dipole and the rotating-wave approximations apply. Furthermore, the single-photon state that leaves the cavity asymptotically is determined. The corresponding time-reversed single-photon quantum state is capable of exciting the atom in this extreme multimode scenario with near-unit probability. Using semiclassical methods, we derive a photon-path representation for the relevant transition amplitudes and show that it constitutes a satisfactory approximation for a wide range of wavelengths.