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arXiv · 0807.2202

Long-lived spin entanglement induced by a spatially correlated thermal bath

Dara P. S. McCutcheon·Ahsan Nazir·Sougato Bose·Andrew J. Fisher
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Abstract

We investigate how two spatially separated qubits coupled to a common heat bath can be entangled by purely dissipative dynamics. We identify a dynamical time scale associated with the lifetime of the dissipatively generated entanglement and show that it can be much longer than either the typical single-qubit decoherence time or the time scale on which a direct exchange interaction can entangle the qubits. We give an approximate analytical expression for the long-time evolution of the qubit concurrence and propose an ion trap scheme in which such dynamics should be observable.

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Dara P. S. McCutcheon, Ahsan Nazir, Sougato Bose, Andrew J. Fisher. 2008-07-14. Long-lived spin entanglement induced by a spatially correlated thermal bath. https://doi.org/10.1103/physreva.80.022337

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