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arXiv · 0903.3464

Generation and propagation of entanglement in driven coupled-qubit systems

Jian Li·G. S. Paraoanu
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Abstract

In a bipartite system subject to decoherence from two separate reservoirs, the entanglement is typically destroyed faster than for single reservoirs. Surprisingly however, the existence of separate reservoirs can also have a beneficial entangling effect: if the qubits are coupled and driven externally by a classical field, the system ends up in a stationary state characterized by a finite degree of entanglement. This phenomenon occurs only in a certain region of the parameter space and the structure of the stationary state has a universal form which does not depend on the initial state or on the specific physical realization of the qubits. We show that the entanglement thus generated can be propagated within a quantum network using simple local unitary operations. We suggest the use of such systems as "batteries of entanglement" in quantum circuits.

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Jian Li, G. S. Paraoanu. 2010-03-01. Generation and propagation of entanglement in driven coupled-qubit systems. https://doi.org/10.1088/1367-2630%2F11%2F11%2F113020

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