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Updated: Jun 2, 2026

A Photonic System for Generating Unconditional Polarization-Entangled Photons Based on Multiple Quantum Interference
Published on: September 5, 2019
Quantum interference and entanglement of photons that do not overlap in time
R Wiegner1, C Thiel, J von Zanthier
1Institut für Optik, Information und Photonik, Universität Erlangen-Nürnberg, Erlangen, Germany. ralph.wiegner@physik.uni‐erlangen.de
Abstract:
We discuss the possibility of quantum interferences and entanglement of photons that exist at different intervals of time, i.e., one photon being recorded before the other has been created. The corresponding two-photon correlation function is shown to violate Bell's inequalities.
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