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Updated: Jul 31, 2025
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A Photonic System for Generating Unconditional Polarization-Entangled Photons Based on Multiple Quantum Interference
Published on: September 5, 2019
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Testing entanglement of annihilation photons
Alexander Ivashkin1, Dzhonrid Abdurashitov2, Alexander Baranov2,3
1Institute for Nuclear Research RAS, Moscow, 117312, Russia. ivashkin@inr.ru.
Scientific Reports
|May 10, 2023
Summary
This study explores quantum entanglement in high-energy photon pairs from positron-electron annihilation. Pre-scattering photons before measurement did not alter their quantum correlations, supporting quantum measurement theory.
Area of Science:
- Quantum Physics
- High-Energy Physics
- Quantum Optics
Background:
- Positron-electron annihilation produces entangled photon pairs.
- High-energy photons allow for novel experimental manipulations like Compton pre-scattering.
- Understanding polarization correlations is crucial for quantum information science.
Purpose of the Study:
- To experimentally investigate quantum entanglement of high-energy photon pairs.
- To explore the effect of Compton pre-scattering on photon polarization correlations.
- To compare polarization correlations before and after pre-scattering.
Main Methods:
- Producing entangled photon pairs via positron-electron annihilation at rest.
- Utilizing Compton polarimeters to measure photon angular correlations.
- Performing a direct comparison of polarization correlations in initial and pre-scattered states.
Main Results:
- The angular distributions of scattered photons were identical for initial and pre-scattered states.
- The correlation function within Bell's inequality remained unchanged after pre-scattering.
- This marks the first direct comparison of polarization correlations in these states.
Conclusions:
- Compton pre-scattering does not affect the measured quantum correlations of entangled photons.
- Results have implications for quantum measurement theory.
- Findings may advance quantum-entangled positron emission tomography.
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