THEORETICAL INVESTIGATION OF TRANSMISSION THROUGH A FARADAY-ACTIVE FABRY-PEROT ETALON

The multiple-beam summation method is used to construct a Fabry-Perot-cavity theory that takes into consideration the Faraday rotation effect. The transmission functions and the state of the polarizations are derived and discussed for the resonant and the off-resonant cavity configurations. The transmission function that includes the analyzer is also derived and discussed. The results in resonance configuration agree with the early theoretical and experimental results: mainly that the Faraday rotation can be resonantly enhanced by the Fabry-Perot cavity. In the off-resonance configuration the transmission as a function of the single-trip phase consists of two Airy functions separated by a distance of twice of the single-trip Faraday rotation. In the high reflectivity limit, the light at the peak becomes quasi-circularly polarized. The effect of this resonant structure on the Fabry-Perot cavity as a spectroscopic tool is mentioned.