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

Abstract

Within the framework of macroscopic quantum electrodynamics, the resonant van der Waals potential experienced by an excited two-level atom near a planar magnetoelectric two-layer system consisting of a slab of left-handed material and a perfect mirror is studied. It is shown that the disregard 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 [K\"astel and Fleischhauer, Phys. Rev. A 68, 011804(R) (2005)] is reconsidered. Disregard of absorption is shown to drastically falsify the dependence on the atomic position of the decay rate.