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arXiv · 1507.05007

Non-equilibrium steady-states in a driven-dissipative superfluid

Ralf Labouvie·Bodhaditya Santra·Simon Heun·Herwig Ott
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Abstract

We experimentally study a driven-dissipative Josephson junction array, realized with a weakly interacting Bose Einstein condensate residing in a one-dimensional optical lattice. Engineered losses on one site act as a local dissipative process, while tunneling from the neighboring sites constitutes the driving force. We characterize the emerging steady-states of this atomtronic device. With increasing dissipation strength $γ$ the system crosses from a superfluid state, characterized by a coherent Josephson current into the lossy site to a resistive state, characterized by an incoherent hopping transport. For intermediate values of $γ$, the system exhibits bistability, where a superfluid and a resistive branch coexist. We also study the relaxation dynamics towards the steady-state, where we find a critical slowing down, indicating the presence of a non-equilibrium phase transition.

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Ralf Labouvie, Bodhaditya Santra, Simon Heun, Herwig Ott. 2015-07-17. Non-equilibrium steady-states in a driven-dissipative superfluid. https://doi.org/10.1103/physrevlett.116.235302

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