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arXiv · 1502.07854

Incompressible polaritons in a flat band

Matteo Biondi·Evert P. L. van Nieuwenburg·Gianni Blatter·Sebastian D. Huber·Sebastian Schmidt
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Abstract

We study the interplay of geometric frustration and interactions in a non-equilibrium photonic lattice system exhibiting a polariton flat band as described by a variant of the Jaynes-Cummings-Hubbard model. We show how to engineer strong photonic correlations in such a driven, dissipative system by quenching the kinetic energy through frustration. This produces an incompressible state of photons characterized by short-ranged crystalline order with period doubling. The latter manifests itself in strong spatial correlations, i.e., on-site and nearest-neighbor anti-bunching combined with extended density-wave oscillations at larger distances. We propose a state-of-the-art circuit QED realization of our system, which is tunable in situ.

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Matteo Biondi, Evert P. L. van Nieuwenburg, Gianni Blatter, Sebastian D. Huber, Sebastian Schmidt. 2015-09-21. Incompressible polaritons in a flat band. https://doi.org/10.1103/physrevlett.115.143601

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