Axion-plasmon polaritons in strongly magnetized plasmas

TL;DR

This paper proposes the existence of axion-plasmon polaritons in strongly magnetized plasmas, suggesting a new way to detect axions and exploring their potential role in astrophysical phenomena.

Contribution

It introduces the concept of axion-plasmon polaritons and analyzes their dispersion relations and stability in extreme plasma conditions, linking particle physics and astrophysics.

Findings

Axion-plasmon polaritons modify Langmuir wave dispersion relations.

Detection of axions could be feasible in current plasma experiments.

Instability of these polaritons in dense neutron star interiors suggests a mechanism for axion-like particle creation.

Abstract

Axions are hypothetical particles related to the violation of the charge-parity symmetry, being the most prone candidates for dark matter. Multiple attempts to prove their existence are currently performed in different physical systems. Here, we anticipate the possibility of the axions coupling to the electrostatic (Langmuir) modes of a strongly magnetized plasma, by showing that a new quasi-particle can be defined, the axion-plasmon polariton. The excitation of axions can be inferred from the pronounced modification of the dispersion relation of the Langmuir waves, a feature that we estimate to be accessible in state-of-the-art plasma-based experiments. We further show that, under extreme density and magnetic field conditions (e.g. at the interior of dense neutron stars), the axion-plasmon polariton becomes dynamically unstable, similarly to the case of the Jeans instability occurring in self-gravitating fluids. This latter result anticipates a plausible mechanism to the creation of axion-like particles in the universe.