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Updated: Jun 19, 2026

A Photonic System for Generating Unconditional Polarization-Entangled Photons Based on Multiple Quantum Interference
Published on: September 5, 2019
Coherent rho;{0} photoproduction in bulk matter at high energies
1Lawrence Berkeley National Laboratory, Berkeley, California, 94720, USA.
Abstract:
The momentum transfer Deltak required for a photon to scatter from a target and emerge as a rho;{0} decreases as the photon energy k rises. For k > 3 x 10;{14} eV, Deltak is small enough that the interaction cannot be localized to a single nucleus. At still higher energies, photons may coherently scatter elastically from bulk matter and emerge as a rho;{0}, in a manner akin to kaon regeneration. Constructive interference from the different nuclei coherently raises the cross section and the interaction probability rises linearly with energy. At energies above 10;{23} eV, coherent conversion is the dominant process; photons interact predominantly as rho;{0}. We compute the coherent scattering probabilities in slabs of lead, water, and rock, and discuss the implications of the increased hadronic interaction probabilities for photons on ultrahigh energy shower development.
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