Light polarization oscillations induced by photon-photon scattering

TL;DR

This paper investigates how quantum photon-photon interactions can cause vacuum electromagnetic waves to oscillate between different polarizations, revealing potential observable effects in optical experiments.

Contribution

It introduces a multiscale analytical approach to describe polarization oscillations caused by photon-photon scattering in vacuum.

Findings

Electromagnetic waves exhibit polarization oscillations due to photon-photon scattering.

Secularities in the dynamical equations indicate wave instability in certain configurations.

Periodic polarization oscillations could be detectable in optical experiments.

Abstract

We consider the Heisenberg-Euler action for an electromagnetic field in vacuum, which includes quantum corrections to the Maxwell equations induced by photon-photon scattering. We show that, in some configurations, the plane monochromatic waves become unstable, due to the appearance of secularities in the dynamical equations. These secularities can be treated using a multiscale approach, introducing a slow time variable. The amplitudes of the plane electromagnetic waves satisfy a system of ordinary differential nonlinear equations in the slow time. The analysis of this system shows that, due to the effect of photon-photon scattering, in the unstable configurations the electromagnetic waves oscillate periodically between left-hand-sided and right-hand-sided polarizations. Finally, we discuss the physical implications of this finding, and the possibility of disclosing traces of this effect in optical experiments.