Position dependent energy level shifts of an accelerated atom in the presence of a boundary

TL;DR

This paper investigates how uniform acceleration and boundary conditions affect atomic energy levels, revealing that accelerated atoms do not simply mimic thermal baths and highlighting specific regimes where acceleration impacts energy shifts.

Contribution

It provides a detailed analysis of position-dependent energy level shifts of an accelerated atom near a boundary, including vacuum fluctuation and radiation reaction contributions, and compares with existing literature.

Findings

Accelerated atoms do not behave as if in a thermal bath at the Unruh temperature.

Acceleration effects on energy shifts can be significant under certain conditions.

Differences from previous studies are observed when acceleration is comparable to atomic transition frequencies.

Abstract

We consider a uniformly accelerated atom interacting with a vacuum electromagnetic field in the presence of an infinite conducting plane boundary and calculate separately the contributions of vacuum fluctuations and radiation reaction to the atomic energy level shift. We analyze in detail the behavior of the total energy shift in three different regimes of the distance in both the low acceleration and high acceleration limits. Our results show that, in general, an accelerated atom does not behave as if immersed in a thermal bath at the Unruh temperature in terms of the atomic energy level shifts, and the effect of the acceleration on the atomic energy level shifts may in principle become appreciable in certain circumstances, although it may not be realistic for actual experimental measurements. We also examine the effects of the acceleration on the level shifts when the acceleration is of the order of the transition frequency of the atom and we find some features differ from what was obtained in the existing literature.