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arXiv · 1705.02889

Superradiant to subradiant phase transition in the open system Dicke model: Dark state cascades

Michael Gegg·Alexander Carmele·Andreas Knorr·Marten Richter
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Abstract

Collectivity in ensembles of atoms gives rise to effects like super- and subradiance. While superradiance is well studied and experimentally accessible, subradiance remains elusive since it is difficult to track experimentally as well as theoretically. Here we present a new type of phase transition in the resonantly driven, open Dicke model that leads to a deterministic generation of subradiant states. At the transition the system switches from a predominantly superradiant to a predominantly subradiant state. Clear experimental signatures for the effect are presented and entanglement properties are discussed. Letting the system relax into the ground state generates a cascade of dark Dicke states, with dark state populations up to unity. Furthermore we introduce a collectivity measure that allows to quantify collective behavior.

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Michael Gegg, Alexander Carmele, Andreas Knorr, Marten Richter. 2017-07-12. Superradiant to subradiant phase transition in the open system Dicke model: Dark state cascades. https://doi.org/10.1088/1367-2630%2Faa9cdd

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