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arXiv · 0707.4092

Protection of entanglement from sudden death using continuous dynamical decoupling

F. F. Fanchini·R. d. J. Napolitano
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Abstract

We show that continuous dynamical decoupling can protect a two-qubit entangled state from sudden death at finite temperature due to uncorrelated dephasing, bit flipping, and dissipation. We consider a situation where an entangled state shared between two non-interacting qubits is initially prepared and left evolve under the environmental perturbations and the protection of external fields. To illustrate the protection of the entanglement, we solve numerically a master equation in the Born approximation, considering independent boson fields at the same temperature coupled to the different error agents of each qubit.

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F. F. Fanchini, R. d. J. Napolitano. 2007-07-27. Protection of entanglement from sudden death using continuous dynamical decoupling. https://doi.org/10.1103/physreva.76.062306

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