Polarization conversion in resonant magneto-optic gratings

Strong polarization conversion effects, including large Kerr rotation and ellipticity, are predicted in zero-order reflection of light from a Bi : YIG grating embedded in a dielectric material. The field localization that gives rise to the enhanced magneto-optic effects is due to the excitation of leaky guided waves, which propagate in (and around) the high-index Bi : YIG layer in directions perpendicular to the external static magnetic field as well as the incident, transmitted and reflected optical fields. The resonant interaction with the incident field then results in narrow-band reflection spectra. Large magneto-optic polarization conversion effects result from the splitting of the degeneracy of right- and left-circularly polarized eigenmode resonances with highly dispersive phase spectra near the resonance peak.