Résumé |
The Heisenberg-Euler formula, describing the non-linear effective action of photon, is generalized to include parity violating effects. Using the formula, how to probe the dark sector via the magnetic birefringence experiments is studied, in which a new scheme has emerged. The scheme uses a ring Fabry-P¥'erot resonator which can measure the parity violating effects directly without QED background. As an example, the sensitivity of the measurements (ellipticity and polarization rotation) is given, in the presence of a dark sector neutrino, as a function of a mixing parameter between visible and dark sectors and the mass of the dark sector neutrino. |