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arXiv · 1904.08135

Observation of PT-symmetric quantum interference

Friederike U. J. Klauck·Lucas Teuber·Marco Ornigotti·Matthias Heinrich·Stefan Scheel·Alexander Szameit
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Abstract

Parity-Time (PT) symmetric quantum mechanics is a complex extension of conventional Hermitian quantum mechanics in which physical observables possess a real eigenvalue spectrum. However, an experimental demonstration of the true quantum nature of PT symmetry has been elusive thus far, as only single-particle physics has been exploited to date. In our work, we demonstrate two-particle quantum interference in a PT-symmetric system. We employ integrated photonic waveguides to reveal that PT-symmetric bunching of indistinguishable photons shows strongly counterintuitive features. We substantiate our experimental results by modelling the system by a quantum master equation, which we analytically solve using Lie algebra methods. Our work paves the way for nonlocal PT-symmetric quantum mechanics as a novel building block for future quantum devices.

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Friederike U. J. Klauck, Lucas Teuber, Marco Ornigotti, Matthias Heinrich, Stefan Scheel, Alexander Szameit. 2019-04-17. Observation of PT-symmetric quantum interference. https://doi.org/10.1038/s41566-019-0517-0

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