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arXiv · 2007.08938

Out-of-equilibrium steady states of a locally driven lossy qubit array

Abstract

We find a rich variety of counterintuitive features in the steady states of a qubit array coupled to a dissipative source and sink at two arbitrary sites, using a master equation approach. We show there are setups where increasing the pump and loss rates establishes long-range coherence. At sufficiently strong dissipation, the source or sink effectively generates correlation between its neighboring sites, leading to a striking density-wave order for a class of "resonant" geometries. This effect can be used more widely to engineer nonequilibrium phases. We show the steady states are generically distinct for hard-core bosons and free fermions, and differ significantly from the ones found before in special cases. They are explained by generally applicable ansatzes for the long-time dynamics at weak and strong dissipation. Our findings are relevant for existing photonic setups.

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Shovan Dutta, Nigel R. Cooper. 2020-07-17. Out-of-equilibrium steady states of a locally driven lossy qubit array. https://doi.org/10.1103/physrevresearch.3.l012016

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