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arXiv · 0908.0958

Decoherence suppression via environment preparation

Olivier Landon-Cardinal·Richard MacKenzie
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Abstract

To protect a quantum system from decoherence due to interaction with its environment, we investigate the existence of initial states of the environment allowing for decoherence-free evolution of the system. For models in which a two-state system interacts with a dynamical environment, we prove that such states exist if and only if the interaction and self-evolution Hamiltonians share an eigenstate. If decoherence by state preparation is not possible, we show that initial states minimizing decoherence result from a delicate compromise between the environment and interaction dynamics.

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Olivier Landon-Cardinal, Richard MacKenzie. 2009-08-06. Decoherence suppression via environment preparation. https://doi.org/10.1103/physreva.80.062319

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