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arXiv · 1503.03146

Phase diagram of a QED-cavity array coupled via a N-type level scheme

Jiasen Jin·Rosario Fazio·Davide Rossini
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Abstract

We study the zero-temperature phase diagram of a one-dimensional array of QED cavities where, besides the single-photon hopping, an additional coupling between neighboring cavities is mediated by an N-type four-level system. By varying the relative strength of the various couplings, the array is shown to exhibit a variety of quantum phases including a polaritonic Mott insulator, a density-wave and a superfluid phase. Our results have been obtained by means of numerical density-matrix renormalization group calculations. The phase diagram was obtained by analyzing the energy gaps for the polaritons, as well as through a study of two-point correlation functions.

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Jiasen Jin, Rosario Fazio, Davide Rossini. 2015-03-11. Phase diagram of a QED-cavity array coupled via a N-type level scheme. https://doi.org/10.1140/epjqt/s40507-015-0018-0

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