A. V. Kats

Resonantly suppressed transmission and anomalously enhanced light absorption in periodically modulated ultrathin metal films

We study light diffraction in the periodically modulated ultrathin metal films both analytically and numerically. Without modulation these films are almost transparent. The periodicity results in the anomalous effects, such as suppression of the transmittance accompanied by a strong enhancement of the absorptivity and specular reflectivity, due to excitation of the surface plasmon polaritons. These phenomena are opposite to the widely known enhanced transparency of periodically modulated optically thick metal films. Our theoretical analysis can be a starting point for the experimental investigation of these intriguing phenomena.

Extraordinary optical transmission through hole arrays in optically thin metal films

A theoretical study is presented on the optical transmission through square hole arrays drilled in optically thin films, where transmission may occur through both the holes and the metal layer. It is shown that, as the thickness of the metal film decreases, the coupling of light with short-range surface plasmons redshifts the extraordinary optical transmission peak to longer wavelengths. At the same time, the maximum-to-minimum transmittance ratio is kept high even for metal thicknesses as small as one skin depth.

Resonance effects due to the excitation of surface Josephson plasma waves in layered superconductors

We analytically examine the excitation of surface Josephson plasma waves (SJPWs) in layered superconductors by an incident electromagnetic wave. The mechanism of excitation is related to the diffraction of the incident wave due to a small periodic modulation in the

Nonzeroth-Order Anomalous Optical Transparency in Modulated Metal Films Owing to Excitation of Surface Plasmon Polaritons: An Analytic Approach ¶

\mathbf{a}\mathbf{b}

Analytical investigation of the spectra of coupled polaritons on double periodic metal surfaces

plane of the maximum

Resonance effects due to exitation of the surface waves in periodically-modulated layered superconductors

\mathbf{c}

Surface Josephson Plasma Waves in Layered HTC Superconductors and their Excitation via Attenuated Total Reflection

-axis Josephson current density. We show that the absorption of the incident wave can be substantially increased, for certain incident angles, due to the resonance excitation of SJPWs. The absorption increase is accompanied by a decrease in the specular reflection. Moreover, we find the dependence of the resonance value of the incident angle on the parameters of the superconductor and the frequency of the incident wave, and the depth of the modulations guaranteeing the total absorption (and total suppression of the specular reflection). Numerical examples of the resonance effects are presented for Bi2212 superconductors.

Anomalous Optical Effects Under Resonance Excitation of Surface Plasmons in 2D Periodically Modulated Metal Films

The problem of anomalous light tunneling through periodically modulated metal films is examined in a purely analytical approach. The approach uses large magnitude of the dielectric permittivity of metals in the visible and near-infrared (it is equivalent to that resulting in the Leontovich boundary conditions for semi-infinite problems). It is shown that the anomalous transparency recently discovered experimentally is caused by the excitation of single-or double-boundary surface plasmon polaritons due to film modulation. Dependences of the resonance transparency on parameters of the problem are analyzed in detail, and the optimum parameters (optimal layer thickness and optimal modulation amplitude) corresponding to extreme values of the transmittance of both zero and nonzero diffraction orders have been found. Classifying the possible types of resonances has allowed the identification of special and nontrivial features of the effect. In particular, we predict strong nonzeroth-order anomalous transparency.

An analytical study of 2D photonic structures

The results of analytical and numerical investigation of the surface plasmon-polaritons (SPP)dispersion relation on double periodical high reflecting surfaces (two-dimensional photonic crystals)are presented. The formalism is developed for gratings formed by the modulation of either optical properties or the relief of the medium. The coupling between SPP existing on the non-modulated boundary leads to the mini-gaps arising at the Brillouin-zone boundaries. The dependence of the dispersion relation upon the parameters of the problem (amplitude of the modulation, an angle between the elementary translations,etc.) is calculated for different types of symmetry that corresponds to the coupling from two to six polaritons. The specific values of the parameters corresponding to existence of the standing polariton modes, vanishing of the polariton group velocity are found. The distribution of surface charges for corresponding polariton modes is presented. The ratio between the polariton dispersion relation and the light diffraction under the condition of the polariton excitation is discussed as well. The results obtained can be used to design the two-dimensional photonic crystals with specific and given properties.

Anomalous optical properties of absorptive modulated metal film under surface plasmon polariton excitation conditions

In this paper the surface Josephson plasma wave (SJPW) excitation on the periodically-modulated layered superconductor is considered. It is shown that the absorption of the incident electromagnetic wave can be substantially increased at certain incident angles due to the resonance excitation of the surface waves. The optimal combinations of the parameters of the problem (modulation amplitude, wavelength, incident angle) corresponding to maximum SJPW excitation and the effect of the total suppression of specular reflection (TSSR) are found for a real medium (Bi2212).