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arXiv · 1901.05756

Time-optimal purification of a qubit in contact with a structured environment

Jonas Fischer·Daniel Basilewitsch·Christiane P. Koch·Dominique Sugny
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Abstract

We investigate the time-optimal control of the purification of a qubit interacting with a structured environment, consisting of a strongly coupled two-level defect in interaction with a thermal bath. On the basis of a geometric analysis, we show for weak and strong interaction strengths that the optimal control strategy corresponds to a qubit in resonance with the reservoir mode. We investigate when qubit coherence and correlation between the qubit and the environment speed-up the control process.

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Jonas Fischer, Daniel Basilewitsch, Christiane P. Koch, Dominique Sugny. 2019-01-17. Time-optimal purification of a qubit in contact with a structured environment. https://doi.org/10.1103/physreva.99.033410

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