arXiv:0710.3576 · Physical Review B

Entanglement between charge qubits induced by a common dissipative environment

L. Debora Contreras-Pulido, Ramón Aguado

Published Apr 14, 2008• 70 citations

Abstract

We study entanglement generation between two charge qubits due to the strong coupling with a common bosonic environment (Ohmic bath). The coupling to the boson bath is a source of both quantum noise (leading to decoherence) and an indirect interaction between qubits. As a result, two effects compete as a function of the coupling strength with the bath: entanglement generation and charge localization induced by the bath. These two competing effects lead to a nonmonotonic behavior of the concurrence as a function of the coupling strength with the bath and, importantly, to steady-state entanglement. As an application, we present results for charge qubits based on double quantum dots.

DOI: 10.1103/physrevb.77.155420

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