Optical Tamm states at the interface between a photonic crystal and a gyroid layer

The spectral properties of a one-dimensional photonic crystal bounded by an absorbing plasmonic gyroid layer are investigated. The gyroid material is a foam-like metallic three-dimensionally periodic curved film with zero mean curvature at every point. We calculate the transmittance and reflectance spectra at the normal and oblique light incidence. The possibility of the Tamm state formation at the interface between a photonic crystal and a plasmonic gyroid layer caused by the negative real part of the gyroid permittivity is demonstrated for the first time. Specific features of field localization at the Tamm state frequencies are discussed. It is shown that the spectral and polarization properties of the optical Tamm states are highly sensitive to the change in the angle of incidence and in the refractive index of a medium filling the gyroid cavities.