Entanglement control via reservoir engineering in ultracold atomic gases

¹ SUPA, EPS/Physics, Heriot-Watt University - Edinburgh, EH14 4AS, UK, EU
² Turku Center for Quantum Physics, Department of Physics and Astronomy, University of Turku FIN20014, Turku, Finland, EU
³ Centre for Theoretical Atomic, Molecular and Optical Physics, School of Mathematics and Physics, Queens University - Belfast BT7 1NN, UK, EU
⁴ NEST Istituto Nanoscienze-CNR and Dipartimento di Fisica e Chimica, Università degli Studi di Palermo via Archirafi 36, I-90123 Palermo, Italy, EU

Received: 29 November 2012
Accepted: 28 February 2013

Abstract

We study the entanglement of two impurity qubits immersed in a Bose-Einstein condensate (BEC) reservoir. This open quantum system model allows for interpolation between a common dephasing scenario and an independent dephasing scenario by modifying the wavelength of the superlattice superposed to the BEC, and how this influences the dynamical properties of the impurities. We demonstrate the existence of rich dynamics corresponding to different values of reservoir parameters, including phenomena such as entanglement trapping, revivals of entanglement, and entanglement generation. In the spirit of reservoir engineering, we present the optimal BEC parameters for entanglement generation and trapping, showing the key role of the ultracold-gas interactions.