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arXiv:1507.06909 · Physical Review A

Atomic loss and gain as a resource for nonequilibrium phase transitions in optical lattices

Benjamin Everest, Matteo Marcuzzi, Igor Lesanovsky

Published Feb 9, 2016• 10 citations
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Abstract

Directed-percolation-like phase transitions are proposed and analyzed in out-of-equilibrium atomic gases with locally excited Rydberg atoms, which illuminates the emergence of unexpected, soft-matter-like universal behavior in such open quantum systems.
DOI
10.1103/physreva.93.023409

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The directed percolation universality class possibly represents the simplest instance of a genuine non-equilibrium phase transition from an absorbing state to a fluctuating active phase. It is often thought to be as fundamental as the Ising universality class is for equilibrium. However, despite being known for several decades, it has been challenging to find experimental systems that manifest this transition. Here we show theoretically that signatures of the directed percolation universality class emerge in ensembles of strongly interacting Rydberg atoms. We demonstrate that even mesoscopic ensembles --- which are currently studied experimentally --- are sufficient to observe traces of this non-equilibrium phase transition in one, two and three dimensions.
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