# Quantum States and Phases in Driven Open Quantum Systems with Cold Atoms - Quantum Physics

Abstract: An open quantum system, whose time evolution is governed by a masterequation, can be driven into a given pure quantum state by an appropriatedesign of the system-reservoir coupling. This points out a route towardspreparing many body states and non-equilibrium quantum phases by quantumreservoir engineering. Here we discuss in detail the example of a \emph{drivendissipative Bose Einstein Condensate} of bosons and of paired fermions, whereatoms in an optical lattice are coupled to a bath of Bogoliubov excitations viathe atomic current representing \emph{local dissipation}. In the absence ofinteractions 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 understoodas a depletion of the condensate, and in 1D and 2D exhibits propertiesreminiscent of a Luttinger liquid or a Kosterlitz-Thouless critical phase atfinite temperature, with the role of the finite temperature- played by theinteractions.

Author: S. Diehl 1,2, A. Micheli 1,2, A. Kantian 1,2, B. Kraus 1,2, H.P. Büchler 3, P. Zoller 1,2 1 Institute for Theoretical Physics, U

Source: https://arxiv.org/