-symmetric photonic quantum systems with gain and loss do not exist

@article{Scheel2018symmetricPQ,
  title={-symmetric photonic quantum systems with gain and loss do not exist},
  author={S. Scheel and Alexander Szameit},
  journal={Europhysics Letters},
  year={2018},
  volume={122}
}
We discuss the impact of gain and loss on the evolution of photonic quantum states and find that -symmetric quantum optics in gain/loss systems is not possible. Within the framework of macroscopic quantum electrodynamics we show that gain and loss are associated with non-compact and compact operator transformations, respectively. This implies a fundamentally different way in which quantum correlations between a quantum system and a reservoir are built up and destroyed. 
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53 Citations
Background Citations
12
Methods Citations
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53 Citations

Measurement of photon correlations in PT-symmetric systems

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A BSTRACT — We investigate the propagation of the normal two-photon number state and coherent state of light through a dispersive non-Hermitian bilayer structure composed of gain and loss layers,…

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This work creates an optical APT-symmetric system in a synthetic frequency domain using a conventional fiber without intrinsic gain or loss and experimentally reveals photonic APTs, including energy-difference conservation and synchronized power oscillation, which have not yet been confirmed experimentally in the optical domain.
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