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arXiv · 0905.3344

Strong coupling theory for the Jaynes-Cummings-Hubbard model

S. Schmidt·G. Blatter
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Abstract

We present an analytic strong-coupling approach to the phase diagram and elementary excitations of the Jaynes-Cummings-Hubbard model describing a superfluid-insulator transition of polaritons in an array of coupled QED cavities. In the Mott phase, we find four modes corresponding to particle/hole excitations with lower and upper polaritons, respectively. Simple formulas are derived for the dispersion relation and spectral weights within a strong-coupling random-phase approximation (RPA). The phase boundary is calculated beyond RPA by including the leading correction due to quantum fluctuations.

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S. Schmidt, G. Blatter. 2009-09-01. Strong coupling theory for the Jaynes-Cummings-Hubbard model. https://doi.org/10.1103/physrevlett.103.086403

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