Impedance matching considerations for ferrite Faraday rotators

When a linearly polarized plane wave propagates from a dielectric medium into a medium with Faraday rotation, a reflected wave will always occur at the interface. This reflection is necessary because the normal-mode wave impedances in the medium with Faraday rotation are nondegenerate, while the equivalent normal-mode wave impedances for the dielectric medium are degenerate. Therefore it is not possible to match both normal modes simultaneously at the interface. This paper investigates the peculiar reflected wave associated with impedance matching of Faraday rotators, and shows that it should have minimal impact on practical devices.