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arXiv · 2012.11991

A Passive $\mathcal{PT}$-Symmetric Floquet-Coupler

Lucas Teuber·Florian Morawetz·Stefan Scheel
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Abstract

Based on a Liouville-space formulation of open systems, we present a solution to the quantum master equation of two coupled optical waveguides with varying loss. The periodic modulation of the Markovian loss of one of them yields a passive $\mathcal{PT}$-symmetric Floquet system that, at resonance, shows a strong reduction of the required loss for the $\mathcal{PT}$ symmetry to be broken. We showcase this transition for a multi-photon state, and we show how to physically implement the modulated loss with reservoir engineering of a set of bath modes.

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Lucas Teuber, Florian Morawetz, Stefan Scheel. 2020-12-22. A Passive $\mathcal{PT}$-Symmetric Floquet-Coupler. https://doi.org/10.1103/physreva.103.063709

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