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arXiv · 1607.05778

$\mathcal{P}\mathcal{T}$-symmetric slowing-down of decoherence

Bartłomiej Gardas·Sebastian Deffner·Avadh Saxena
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Abstract

We investigate $\mathcal{P}\mathcal{T}$-symmetric quantum systems ultra-weakly coupled to an environment. We find that such open systems evolve under $\mathcal{P}\mathcal{T}$-symmetric, purely dephasing and unital dynamics. The dynamical map describing the evolution is then determined explicitly using a quantum canonical transformation. Furthermore, we provide an explanation of why $\mathcal{P}\mathcal{T}$-symmetric dephasing type interactions lead to \emph{critical slowing down of decoherence}. This effect is further exemplified with an experimentally relevant system -- a $\mathcal{P}\mathcal{T}$-symmetric qubit easily realizable, \emph{e.g.}, in optical or microcavity experiments.

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Bartłomiej Gardas, Sebastian Deffner, Avadh Saxena. 2016-07-19. $\mathcal{P}\mathcal{T}$-symmetric slowing-down of decoherence. https://doi.org/10.1103/physreva.94.040101

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