Vacuum birefringence in the field of a current loop and a guided electromagnetic wave

The effect of vacuum birefringence in a magnetic field generated by a laser-driven capacitor-coil generator as well as in field of an electromagnetic wave in a radioguide has been theoretically considered. The resulting ellipticity of a linearly polarized laser beam propagating in the considered field configuration is calculated. The obtained results are compared to the parameters of the PVLAS experiment which aims to observe the effect of magnetic vacuum birefringence experimentally.