Axion mediated photon to dark photon mixing

Understand

The interaction between the dark/mirror sector and the ordinary sector is considered, where the two sectors interact with each other by sharing the same QCD axion field.

• This feature makes the mixing between ordinary and dark/mirror photons in ordinary and dark electromagnetic fields possible.
• Perturbative solutions of the equations of motion describing the evolution of fields in ordinary and dark external magnetic fields are found.
• User-friendly quantities such as transition probability rates and Stokes parameters are derived.