Modal dispersion structure of coupled magneto-optical waveguides with respect to photonic band-gap localization

摘要

We analyze theoretically the modal dispersion structure of N-period planar waveguides with a bilayer unit cell containing thin magnetized metal film. Three basic configurations of external dc magnetic field are discussed: transversal, polar, and longitudinal. On the basis of coordinate-free surface-impedance formalism we derive compact analytical formula for the characteristic transmission matrix of the magnetized layer in case of polar configuration, which is to our knowledge the novel and non-trivial result. We show that increasing the number of periods leads to prohibition of qTE mode guidance, but find it unrealistic to tailor the band structure of the system by magnetizing the metal films. Alternatively, we propose to control polarization states of the guided modes through magnetization.