Passive PT -symmetric Floquet coupler

-symmetric Floquet coupler},
  author={Lucas Teuber and Florian Morawetz and S. Scheel},
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 PT -symmetric Floquet system that, at resonance, shows a strong reduction of the required loss for the 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… 

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