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arXiv · 1804.01265

Purcell-Dicke effect for an atomic ensemble near a surface

Sebastian Fuchs·Stefan Yoshi Buhmann
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Abstract

The emission by an initially completely inverted atomic ensemble in the long-wavelength regime is simultaneously enhanced by both collective effects (Dicke effect) and dielectric environments (Purcell effect), thus giving rise to a combined Purcell-Dicke effect. We study this effect by treating the ensemble of N atoms as a single effective N+1-level 'Dicke atom' which couples to the environment-assisted quantum electrodynamic field. We find that an environment can indeed alter the superradiant emission dynamics, as exemplified using a perfectly conducting plate. As the emission acquires an additional anisotropy in the presence of the plate, we find an associated resonant Casimir-Polder potential for the atom that is collectively enhanced and that exhibits a superradiant burst in its dynamics. An additional tuneability of the effect is introduced by applying an external driving laser field.

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Sebastian Fuchs, Stefan Yoshi Buhmann. 2018-04-04. Purcell-Dicke effect for an atomic ensemble near a surface. https://arxiv.org/abs/1804.01265

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