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arXiv · 1310.6843

Quenched decoherence in qubit dynamics due to strong amplitude-damping noise

Shin-Tza Wu
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Abstract

We study non-perturbatively the time evolution of a qubit subject to amplitude-damping noise. We show that at strong coupling the qubit decoherence can be quenched owing to large environment feedbacks, such that the qubit can evolve coherently even in the long-time limit. As an application, we show that for a quantum channel that consists of two independent qubits subject to uncorrelated local amplitude-damping noises, it can maintain at strong coupling finite entanglement and better than classical teleportation fidelity at long times.

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Shin-Tza Wu. 2014-03-09. Quenched decoherence in qubit dynamics due to strong amplitude-damping noise. https://doi.org/10.1103/physreva.89.034301

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