Polarization-operator approach to optical signatures of axion-like particles in strong laser pulses

TL;DR

This paper investigates how high-intensity laser pulses can be used to detect axion-like particles by analyzing changes in the polarization of probe light, offering new experimental bounds on these particles' properties.

Contribution

It introduces a polarization tensor approach in a plane-wave background to study optical signatures of axion-like particles in strong laser fields, considering pulse shape effects.

Findings

Ellipticity-based bounds are insensitive to pulse shape.

Polarization plane rotation bounds are more affected by pulse shape.

Potential to set new exclusion limits on axion-like particles.

Abstract

Hypothetical oscillations of probe photons into axion-like particles might be revealed by exploiting the strong fields of high-intensity laser pulses. Considering an arbitrary plane-wave background, we determine the polarization tensor induced by the quantum fluctuations of the axion field and use it to calculate how the polarimetric properties of an initially linear-polarized probe beam are modified. We find that various experimental setups based on contemporary facilities and instrumentation might lead to new exclusion bounds on the parameter space of these particle candidates. The impact of the pulse shape on the discovery potential is studied via a comparison between the cases in which the wave is modulated by a Gaussian envelope and a $\sin^2$ profile. This analysis shows that the upper limits resulting from the ellipticity are relatively insensitive to this change, whereas those arising from the rotation of the polarization plane turn out to be more dependent on the field shape.