Coupler-type waveguide polariser using metal island films: its mechanism and design

A coupler-type waveguide polariser using metal island films with buffer layers has been proposed and designed. The phase constants of the waves guided in the island films depend on the polarisation due to the optical anisotropy of the metal island films. By selecting structural parameters so as to match the phase constants of the guided waves in the island films and in a core only for one polarisation beyond the resonance wavelength of the island film, a waveguide polariser with high extinction ratio is expected. Design theory is presented to obtain an efficient polariser.