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arXiv · 1805.10876

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

Stefan Scheel·Alexander Szameit
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Abstract

We discuss the impact of gain and loss on the evolution of photonic quantum states and find that PT-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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Stefan Scheel, Alexander Szameit. 2018-05-28. PT-symmetric photonic quantum systems with gain and loss do not exist. https://doi.org/10.1209/0295-5075/122/34001

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