arXiv:0707.1497 · Physical Review A

Polaritonic characteristics of insulator and superfluid states in a coupled-cavity array

E. K. Twyeffort Irish, C. D. Ogden, M. S. Kim

Published Mar 3, 2008• 55 citations

Abstract

Recent studies of quantum phase transitions in coupled atom-cavity arrays have focused on the similarities between such systems and the Bose-Hubbard model. However, the bipartite nature of the atom-cavity systems that make up the array introduces some differences. In order to examine the unique features of the coupled-cavity system, the behavior of a simple two-site model is studied over a wide range of parameters. Four regions are identified, in which the ground state of the system may be classified as a polaritonic insulator, a photonic superfluid, an atomic insulator, or a polaritonic superfluid.

DOI: 10.1103/physreva.77.033801

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