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arXiv · 0802.2859

Bang-Bang control of a qubit coupled to a quantum critical spin bath

Davide Rossini·Paolo Facchi·Rosario Fazio·Giuseppe Florio·Daniel A. Lidar·Saverio Pascazio·Francesco Plastina·Paolo Zanardi
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Abstract

We analytically and numerically study the effects of pulsed control on the decoherence of a qubit coupled to a quantum spin bath. When the environment is critical, decoherence is faster and we show that the control is relatively more effective. Two coupling models are investigated, namely a qubit coupled to a bath via a single link and a spin star model, yielding results that are similar and consistent.

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Davide Rossini, Paolo Facchi, Rosario Fazio, Giuseppe Florio, Daniel A. Lidar, Saverio Pascazio, Francesco Plastina, Paolo Zanardi. 2008-05-20. Bang-Bang control of a qubit coupled to a quantum critical spin bath. https://doi.org/10.1103/physreva.77.052112

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