Motion induced excitation and radiation from an atom facing a mirror

TL;DR

This paper investigates quantum dissipative effects and radiation from a non-relativistically accelerated atom near a perfect mirror, revealing how motion influences atom-field interactions and emission rates.

Contribution

It provides a detailed analysis of vacuum decay and emission processes for a moving atom near a mirror using a scalar field model, including explicit calculations of transition amplitudes and decay probabilities.

Findings

Vacuum decay probabilities match integrated transition amplitudes.

Spontaneous emission rate for an oscillating atom is computed.

Motion induces excitation and radiation effects in the atom-field system.

Abstract

We study quantum dissipative effects due to the non-relativistic, bounded, accelerated motion of a single neutral atom in the presence of a planar perfect mirror, i.e. a perfect conductor at all frequencies. We consider a simplified model whereby a moving `scalar atom' is coupled to a quantum real scalar field, subjected to either Dirichlet or Neumann boundary conditions on the plane. We use an expansion in powers of the departure of the atom with respect to a static average position, to compute the vacuum persistence amplitude, and the resulting vacuum decay probability. We evaluate transition amplitudes corresponding to the excitation of the atom plus the emission of a particle, and show explicitly that the vacuum decay probabilities match the results obtained by integrating the transition amplitudes over the directions of the emitted particle. We also compute the spontaneous emission rate of an oscillating atom that is initially in an excited state.