Vacuum birefringence in strong inhomogeneous electromagnetic fields

Understand

Birefringence is one of the fascinating properties of the vacuum of quantum electrodynamics (QED) in strong electromagnetic fields.

• The scattering of linearly polarized incident probe photons into a perpendicularly polarized mode provides a distinct signature of the optical activity of the quantum vacuum and thus offers an excellent opportunity for a precision test of non-linear QED.
• Precision tests require accurate predictions and thus a theoretical framework that is capable of taking the detailed experimental geometry into account.
• We derive analytical solutions for vacuum birefringence which include the spatio-temporal field structure of a strong optical pump laser field and an x-ray probe.