# A single trapped atom in front of an oscillating mirror

## TL;DR

This paper studies how a two-level atom's spontaneous decay and emitted light spectrum are affected by an oscillating mirror, revealing complex dependencies on distance and mirror motion parameters, extending static mirror theories.

## Contribution

It extends previous static mirror models by analyzing a moving mirror's impact on atomic decay and emission spectra, incorporating non-stationary field effects.

## Key findings

- Spectrum depends on mirror-atom distance and oscillation parameters.
- Decay rates and level shifts are significantly affected by mirror motion.
- The work lays groundwork for quantum motion effects in atom-mirror systems.

## Abstract

We investigate the Wigner-Weisskopf decay of a two level atom in front of an oscillating mirror. This work builds on and extends previous theoretical and experimental studies of the effects of a static mirror on spontaneous decay and resonance fluorescence. The spontaneously emitted field is inherently non-stationary due to the time-dependent boundary conditions and in order to study its spectral distribution we employ the operational definition of the spectrum of non-stationary light due to the seminal work by Eberly and Wodkiewicz. We find a rich dependence of this spectrum as well as of the effective decay rates and level shifts on the mirror-atom distance and on the amplitude and frequency of oscillations of the mirror. The results presented here provide the basis for future studies of more complex setups, where the motion of the atom and/or the mirror are included as quantum degrees of freedom.