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arXiv · 1807.11502

Inducing nontrivial qubit coherence through a controlled dispersive environment

W. S. Teixeira·F. Nicacio·F. L. Semião
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Abstract

We show how the dispersive regime of the Jaynes-Cummings model may serve as a valuable tool to the study of open quantum systems. We employ it in a bottom-up approach to build an environment that preserves qubit energy and induces varied coherence dynamics. We then present the derivation of a compact expression for the qubit coherence, applied here to the case of a finite number of thermally populated modes in the environment. We also discuss how the model parameters can be adjusted to facilitate the production of short-time monotonic decay (STMD) of the qubit coherence. Our results provide a broadly applicable platform for the investigation of energy-conserving open system dynamics which is fully within the grasp of current quantum technologies.

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W. S. Teixeira, F. Nicacio, F. L. Semião. 2019-03-07. Inducing nontrivial qubit coherence through a controlled dispersive environment. https://doi.org/10.1103/physreva.99.032102

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