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arXiv · 1510.06651

Beyond mean-field bistability in driven-dissipative lattices: bunching-antibunching transition and quantum simulation

J. J. Mendoza-Arenas·S. R. Clark·S. Felicetti·G. Romero·E. Solano·D. G. Angelakis·D. Jaksch
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Abstract

In the present work we investigate the existence of multiple nonequilibrium steady states in a coherently driven XY lattice of dissipative two-level systems. A commonly used mean-field ansatz, in which spatial correlations are neglected, predicts a bistable behavior with a sharp shift between low- and high-density states. In contrast one-dimensional matrix product methods reveal these effects to be artifacts of the mean-field approach, with both disappearing once correlations are taken fully into account. Instead, a bunching-antibunching transition emerges. This indicates that alternative approaches should be considered for higher spatial dimensions, where classical simulations are currently infeasible. Thus we propose a circuit QED quantum simulator implementable with current technology to enable an experimental investigation of the model considered.

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J. J. Mendoza-Arenas, S. R. Clark, S. Felicetti, G. Romero, E. Solano, D. G. Angelakis, D. Jaksch. 2016-02-16. Beyond mean-field bistability in driven-dissipative lattices: bunching-antibunching transition and quantum simulation. https://doi.org/10.1103/physreva.93.023821

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