The annihilation quantum entanglement experiments

F. J. Duarte

F.J. Duarte

P. Knights, Finlay Ryburn, G. Tungate +1 more

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.

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.

F. J. Duarte

F. J. Duarte