Optical Tamm states localized at the edges of a photonic crystal bounded from one or both sides by a nanocomposite have been studied. The nanocomposite consists of metallic nanoinclusions, which have...

The possibility of using a hyperbolic metamaterial to form conventional and epsilon-near-zero Tamm plasmon polaritons in the near-infrared and visible spectral ranges is demonstrated. The spectral properties of the hyperbolic metamaterial are investigated in the framework of the effective medium theory and confirmed by the transfer matrix method. It is found that at the oblique incidence of light onto a structure, the I-type hyperbolic metamaterial can be implemented, while II-type cannot. The sensitivity of the epsilon-near-zero wavelength to the variation in the angle of light incidence for TE and TM waves is demonstrated. It is shown that both the high-quality and broadband Tamm plasmon polaritons are excited in the investigated structures.

Two schemes of excitation of a Tamm plasmon polariton localized at the interface between a photonic crystal and a nanocomposite with near-zero effective permittivity have been investigated in the framework of the temporal coupled-mode theory. The parameters of the structure have been determined, which correspond to the critical coupling of the incident field with a Tamm plasmon polariton and, consequently, ensure the total absorption of the incident radiation by the structure. It has been established that the spectral width of the absorption line depends on the scheme of Tamm plasmon polariton excitation and the parameters of a nanocomposite film. The features of field localization at the Tamm plasmon polariton frequency for different excitation schemes have been examined. It has been demonstrated that such media can be used as narrowband absorbers based on Tamm plasmon polaritons localized at the interface between a photonic crystal and a nanocomposite with near-zero effective permittivity.

We investigate optical Tamm states supported by a dielectric grating placed on top of a distributed Bragg reflector. It is found that under certain conditions the Tamm state may become a bound state in the continuum. The bound state, in its turn, induces the effect of critical coupling with the reflectance amplitude reaching an exact zero. We demonstrate that the critical coupling point is located in the core of a vortex of the reflection amplitude gradient in the space of the wavelength and angle of incidence. The emergence of the vortex is explained by the coupled mode theory.

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.