Van der Waals interaction and spontaneous decay of an excited atom in a superlens-type geometry

TL;DR

This paper investigates the van der Waals interaction and spontaneous decay of an excited atom near a superlens-type structure, emphasizing the importance of material absorption for accurate physical predictions.

Contribution

It provides a detailed analysis of the atom-surface interaction in a superlens geometry, highlighting the critical role of absorption and proposing potential applications like particle levitation.

Findings

Disregarding absorption leads to unphysical divergence in potential.

A potential barrier can be formed for particle trapping.

Absorption significantly affects the decay rate dependence.

Abstract

Within the framework of macroscopic quantum electrodynamics, the resonant van der Waals potential experienced by an excited two-level atom near a planar magneto-electric two-layer system consisting of a slab of left-handed material and a perfect mirror is studied. It is shown that disregarding of material absorption leads to unphysical results, with divergent values for the potential away from the surface. Under appropriate conditions, the setup is found to feature a barrier near the surface which can be employed to levitate particles or used as a trapping or cooling mechanism. Finally, the problem of spontaneous decay [J. K\"{a}stel and M. Fleischhauer, Phys. Rev. A \textbf{68}, 011804(R) (2005)] is revisited. Disregarding of absorption is shown to drastically falsify the dependence on the atomic position of the decay rate.