Vacuum Birefringence in a Supercritical Magnetic Field

Abstract

The birefringence effect in vacuum in strong magnetic fields has been considered. The polarization tensor in a constant external magnetic field is analyzed in the framework of quantum field theory and on the basis of the electron Green’s function calculated as the sum over the Landau levels. The case of the lowest Landau levels for photons with the energies below the electron-positron pair creation threshold is considered, and the corresponding refractive indices of the physical vacuum for anomalous and normal waves are determined.

Electron-Positron Pair Photoproduction in a Strong Magnetic Field Through the Polarization Cascade

“…In works [18,19], the resonant case where the intermediate particles reach the mass shell was analyzed. In work [20], the polarization tensor was studied using Green's function in a magnetic field (the tensor is determined by the summation over the Landau levels in the basis of exact solutions of the Dirac equation). The general form of the polarization operator in the lowest-Landau-level approximation was also obtained in work [21] and applied in work [22] to study the magnetic catalysis problem.…”