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Updated: Jul 12, 2025
00:07
A Photonic System for Generating Unconditional Polarization-Entangled Photons Based on Multiple Quantum Interference
Published on: September 5, 2019
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Order-Invariant Two-Photon Quantum Correlations in PT-Symmetric Interferometers
Tom A W Wolterink1, Matthias Heinrich1, Stefan Scheel1
1Institute for Physics, University of Rostock, Albert-Einstein-Straße 23, 18059 Rostock, Germany.
ACS Photonics
|October 23, 2023
Summary
Researchers discovered specific sequences of optical transformations that preserve two-photon behavior, even when the order is reversed. This finding offers new insights into maintaining quantum correlations in complex photonic quantum networks.
Area of Science:
- Quantum optics
- Quantum information science
- Linear optical networks
Background:
- Multiphoton correlations in linear photonic quantum networks are determined by matrix permanents.
- Limited knowledge exists regarding the systematic properties of matrix permanents, hindering intuitive prediction of network behavior.
Purpose of the Study:
- To identify systematic properties of linear optical transformations relevant to multiphoton correlations.
- To find sequences of transformations where two-photon behavior is invariant under order reversal.
Main Methods:
- Investigated sequences of concatenated two-mode linear optical transformations.
- Experimentally verified the identified systematic behavior in parity-time-symmetric complex interferometer arrangements.
Main Results:
- Identified specific sequences of two-mode linear optical transformations exhibiting order-reversal invariance in their two-photon behavior.
- Demonstrated this invariance experimentally in complex interferometer setups.
Conclusions:
- Quantum correlations can be preserved in counterintuitive ways within linear optical networks.
- The findings provide new strategies for designing and controlling quantum correlations in non-Hermitian quantum systems.
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