arXiv:cond-mat/0602063 · Physical Review B

Nonequilibrium entanglement and noise in coupled qubits

Neill Lambert, Ramón Aguado, Tobias Brandes

Published Jan 26, 2007• 78 citations

Abstract

We study the charge entanglement and noise spectrum of two Coulomb-coupled double quantum dots under stationary nonequilibrium transport conditions. In the transport regime, the entanglement exhibits a clear switching threshold and various limits due to suppression of tunneling by quantum Zeno localization or by an interaction-induced energy gap. We also discuss the interdot current correlation as a possible indicator of the entanglement in transport experiments.

DOI: 10.1103/physrevb.75.045340

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