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arXiv · 0803.1482

Quantum States and Phases in Driven Open Quantum Systems with Cold Atoms

S. Diehl·A. Micheli·A. Kantian·B. Kraus·H. P. Büchler·P. Zoller
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Abstract

An open quantum system, whose time evolution is governed by a master equation, can be driven into a given pure quantum state by an appropriate design of the system-reservoir coupling. This points out a route towards preparing many body states and non-equilibrium quantum phases by quantum reservoir engineering. Here we discuss in detail the example of a \emph{driven dissipative Bose Einstein Condensate} of bosons and of paired fermions, where atoms in an optical lattice are coupled to a bath of Bogoliubov excitations via the atomic current representing \emph{local dissipation}. In the absence of interactions the lattice gas is driven into a pure state with long range order. Weak interactions lead to a weakly mixed state, which in 3D can be understood as a depletion of the condensate, and in 1D and 2D exhibits properties reminiscent of a Luttinger liquid or a Kosterlitz-Thouless critical phase at finite temperature, with the role of the ``finite temperature'' played by the interactions.

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S. Diehl, A. Micheli, A. Kantian, B. Kraus, H. P. Büchler, P. Zoller. 2008-03-10. Quantum States and Phases in Driven Open Quantum Systems with Cold Atoms. https://doi.org/10.1038/nphys1073

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