Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

arXiv:1801.07786 · European Journal of Physics

An undergraduate laboratory study of the polarisation of annihilation photons using Compton scattering

P. Knights, Finlay Ryburn, G. Tungate, K. Nikolopoulos

Published Mar 1, 2018• 0 citations
arXivHTMLPDF

Abstract

Abstract An experiment for the advanced undergraduate laboratory which allows students to study the effect of photon polarisation in Compton scattering and to explore quantum entanglement is described. The quantum entangled photons are produced through electron–positron annihilation in the S -state, and their polarisations are analysed using the Compton scattering cross-section dependence on the photon polarisation. The experiment was equipped with off-the-shelf detectors and electronic units. Finite geometry effects are discussed and investigated with the use of a Geant4-based simulation.

DOI
10.1088/1361-6404/aab334

Related papers

Study of the Compton Scattering of Entangled Annihilation Photons

Alexander O. Strizhak, J. N. Abdurashitov, А. Г. Баранов +2 more

Abstract The experimental setup for study of Compton scattering of entangled and decoherent annihilation gammas is described. These gammas are born in two-photon positron-electron annihilation. Polarizations of annihilation gammas are mutually orthogonal, while the polarization of each photon is indefinite. If one of the photons of the pair interacts with matter, the pair becomes decoherent and photons acquire the determined polarization states. The kinematics of Compton scattering depends on the polarization states and can be different for entangled and decoherent pairs of annihilation photons. The angular correlations of scattered gammas for both, entangled and decoherent states are measured and compared. It is shown, that the kinematics of Compton scattering are similar for both cases.

Physics of Particles and Nuclei Letters•Oct 1, 2022•6 citations

Setup of Compton polarimeters for measuring entangled annihilation photons

J. N. Abdurashitov, А. Г. Баранов, D. S. Borisenko +8 more

Abstract An experimental setup for studying the Compton scattering of annihilation photons in various (entangled and decoherent) quantum states is presented. Two entangled γ-quanta with an energy of 511 keV and mutually orthogonal polarizations are produced by positron-electron annihilation in a thin aluminum plate and are emitted in opposite directions. To measure both photons, the setup provides two equivalent arms of Compton polarimeters. A Compton polarimeter consists of a plastic scintillation scatterer and an array of NaI(Tl) detectors for measuring photons deflected at an angle of 90°. The intermediate scatterer of the GAGG scintillator with SiPM readout is inserted into one of the arms to create a tagged decoherence process prior to the measurement of annihilation photons in polarimeters. The performance of Compton scatterers and NaI(Tl) counters is discussed. The polarization modulation factor and the analyzing power of Compton polarimeters are evaluated from the angular distributions of scattered gammas. The Compton scattering of photons in entangled and decoherent states is compared reliably for the first time.

arXiv:2204.04692•Journal of Instrumentation•Mar 1, 2022•22 citations

Monte Carlo Simulation of the Experimental Setup for Studying Entangled Annihilation Photons

Sultan Musin, A. Ivashkin, Alexander O. Strizhak

Abstract This work presents the GEANT4 simulation of the experimental setup for studying the Compton scattering of annihilation photons and compares the simulation results with the experimental data. Two 511 keV photons are born in electron-positron annihilation at rest and have mutually orthogonal polarization which is measured by the system of Compton polarimeters. Each polarimeter consists of scatterer of initial annihilation photons and NaI(Tl) detectors of scattered at 90° photons. Additionally, an intermediate scatterer of GAGG scintillator is used to produce the tagged decoherent photons. Different cases of two-photon quantum states have been simulated. In the first case, the setup response to Compton scattering of entangled photons with mutually perpendicular polarization was studied. In the second case similar study was done for decoherent photons that are produced if one of the initial photons interacts in intermediate scatterer. Distinctions in Compton scattering for these two cases have been obtained and compared to the experimental results. Energy spectra in NaI(Tl) detectors and angular distributions of scattered photons are presented for both entangled and decoherent cases.

Physics of Particles and Nuclei Letters•Dec 1, 2022•1 citation

Testing entanglement of annihilation photons

A. Ivashkin, J. N. Abdurashitov, Alexander Baranov +5 more

We present a new experimental study of the quantum entanglement of photon pairs produced in positron-electron annihilation at rest. Each annihilation photon has an energy that is five orders of magnitude higher than the energy of photons in optical experiments. It provides a unique opportunity for controlled Compton pre-scattering of initial photons before the polarization measurements. The experimental setup includes a system of Compton polarimeters to measure the angular correlations of annihilation photons in initial and thus prepared pre-scattered states. For the first time, a direct comparison of the polarization correlations of initial and pre-scattered annihilation photons has been carried out. The angular distributions of scattered in polarimeters photons turned out to be the same for both types of events. Moreover, the correlation function in the Bell's inequality is also the same for both states. We discuss the implications of our results for quantum measurement theory and for the quantum-entangled positron emission tomography.

arXiv:2210.07623•Scientific Reports•May 9, 2023•55 citations

Setup to study the Compton scattering of entangled annihilation photons

Alexander O. Strizhak, J. N. Abdurashitov, А. Г. Баранов +6 more

The experimental setup to study the difference between Compton scattering of entangled and decoherent annihilation photons is discussed. The pairs of entangled gammas are born in electron-positron annihilation at rest. The polarization state of each photon in such a pair is not definite and represents the superposition of horizontal and vertical polarizations, while the relative polarizations of the photons are orthogonal. After interaction with the environment (for example, via the Compton scattering) the entangled pair of photons is broken and the pair becomes decoherent with determined polarizations of both gammas. Since the Compton scattering depends on the polarization of the initial photon, the scattering kinematics of entangled and decoherent photons might be quite different. At present, there is no experimental comparison of the Compton scattering kinematics for entangled and decoherent gammas.

Journal of Physics Conference Series•Nov 1, 2022•1 citation

Compton scattering mediated by quantum entanglement

Peter Caradonna

In this paper, the 16 Stokes parameters of a two-photon system are organized into a $4\ifmmode\times\else\texttimes\fi{}4$ Stokes matrix. This formalism is then applied to analyze the polarization properties of annihilation photons produced by electron-positron annihilation, with a particular focus on their evolution during Compton scattering interactions. The study demonstrates that when one of the subsystems undergoes Compton scattering, quantum entanglement preserves the polarization symmetry between the scattered and noninteraction photons, while in the absence of entanglement, this symmetry is lost. Moreover, the method simplifies the calculation of the joint differential cross section for multiple scattering scenarios and provides a means to characterize the polarization properties of the individual subsystems. These findings highlight the impact of quantum correlations on scattering behavior, and they offer a framework for further investigation into the polarization dynamics of entangled photon pairs.

Physical Review A•May 8, 2025•9 citations
Abstract An experiment for the advanced undergraduate laboratory which allows students to study the effect of photon polarisation in Compton scattering and to explore quantum entanglement is described. The quantum entangled photons are produced through electron–positron annihilation in the S -state, and their polarisations are analysed using the Compton scattering cross-section dependence on the photon polarisation. The experiment was equipped with off-the-shelf detectors and electronic units. Finite geometry effects are discussed and investigated with the use of a Geant4-based simulation.
Abstract The experimental setup for study of Compton scattering of entangled and decoherent annihilation gammas is described. These gammas are born in two-photon positron-electron annihilation. Polarizations of annihilation gammas are mutually orthogonal, while the polarization of each photon is indefinite. If one of the photons of the pair interacts with matter, the pair becomes decoherent and photons acquire the determined polarization states. The kinematics of Compton scattering depends on the polarization states and can be different for entangled and decoherent pairs of annihilation photons. The angular correlations of scattered gammas for both, entangled and decoherent states are measured and compared. It is shown, that the kinematics of Compton scattering are similar for both cases.
Abstract An experimental setup for studying the Compton scattering of annihilation photons in various (entangled and decoherent) quantum states is presented. Two entangled γ-quanta with an energy of 511 keV and mutually orthogonal polarizations are produced by positron-electron annihilation in a thin aluminum plate and are emitted in opposite directions. To measure both photons, the setup provides two equivalent arms of Compton polarimeters. A Compton polarimeter consists of a plastic scintillation scatterer and an array of NaI(Tl) detectors for measuring photons deflected at an angle of 90°. The intermediate scatterer of the GAGG scintillator with SiPM readout is inserted into one of the arms to create a tagged decoherence process prior to the measurement of annihilation photons in polarimeters. The performance of Compton scatterers and NaI(Tl) counters is discussed. The polarization modulation factor and the analyzing power of Compton polarimeters are evaluated from the angular distributions of scattered gammas. The Compton scattering of photons in entangled and decoherent states is compared reliably for the first time.
Abstract This work presents the GEANT4 simulation of the experimental setup for studying the Compton scattering of annihilation photons and compares the simulation results with the experimental data. Two 511 keV photons are born in electron-positron annihilation at rest and have mutually orthogonal polarization which is measured by the system of Compton polarimeters. Each polarimeter consists of scatterer of initial annihilation photons and NaI(Tl) detectors of scattered at 90° photons. Additionally, an intermediate scatterer of GAGG scintillator is used to produce the tagged decoherent photons. Different cases of two-photon quantum states have been simulated. In the first case, the setup response to Compton scattering of entangled photons with mutually perpendicular polarization was studied. In the second case similar study was done for decoherent photons that are produced if one of the initial photons interacts in intermediate scatterer. Distinctions in Compton scattering for these two cases have been obtained and compared to the experimental results. Energy spectra in NaI(Tl) detectors and angular distributions of scattered photons are presented for both entangled and decoherent cases.
We present a new experimental study of the quantum entanglement of photon pairs produced in positron-electron annihilation at rest. Each annihilation photon has an energy that is five orders of magnitude higher than the energy of photons in optical experiments. It provides a unique opportunity for controlled Compton pre-scattering of initial photons before the polarization measurements. The experimental setup includes a system of Compton polarimeters to measure the angular correlations of annihilation photons in initial and thus prepared pre-scattered states. For the first time, a direct comparison of the polarization correlations of initial and pre-scattered annihilation photons has been carried out. The angular distributions of scattered in polarimeters photons turned out to be the same for both types of events. Moreover, the correlation function in the Bell's inequality is also the same for both states. We discuss the implications of our results for quantum measurement theory and for the quantum-entangled positron emission tomography.
The experimental setup to study the difference between Compton scattering of entangled and decoherent annihilation photons is discussed. The pairs of entangled gammas are born in electron-positron annihilation at rest. The polarization state of each photon in such a pair is not definite and represents the superposition of horizontal and vertical polarizations, while the relative polarizations of the photons are orthogonal. After interaction with the environment (for example, via the Compton scattering) the entangled pair of photons is broken and the pair becomes decoherent with determined polarizations of both gammas. Since the Compton scattering depends on the polarization of the initial photon, the scattering kinematics of entangled and decoherent photons might be quite different. At present, there is no experimental comparison of the Compton scattering kinematics for entangled and decoherent gammas.
In this paper, the 16 Stokes parameters of a two-photon system are organized into a $4\ifmmode\times\else\texttimes\fi{}4$ Stokes matrix. This formalism is then applied to analyze the polarization properties of annihilation photons produced by electron-positron annihilation, with a particular focus on their evolution during Compton scattering interactions. The study demonstrates that when one of the subsystems undergoes Compton scattering, quantum entanglement preserves the polarization symmetry between the scattered and noninteraction photons, while in the absence of entanglement, this symmetry is lost. Moreover, the method simplifies the calculation of the joint differential cross section for multiple scattering scenarios and provides a means to characterize the polarization properties of the individual subsystems. These findings highlight the impact of quantum correlations on scattering behavior, and they offer a framework for further investigation into the polarization dynamics of entangled photon pairs.