![]() Thus, herein, we present analysis performed after the homogenization of the MM corresponding to the MM/dielectric and MM/TCO interfaces. In the case of a spatially infinite anisotropic material, invariant in two directions, the electromagnetic wave dispersion can be plotted for both MM/dielectric and MM/TCO cases. In contrast to extensively studied surface waves such as SPPs and Dyakonov waves, whose in-plane wave vector is greater than that of the bulk modes, the surface waves supported by the nanostructured semiconductor metamaterial cross the light line, and a substantial portion at lower frequencies lies above the free-space light line, which typically separates non-radiative (bound) and radiative (leaky) regions. In this paper, we demonstrate the existence of a new kind of surface wave between two anisotropic metamaterials. Their exotic features give rise to many intriguing applications, such as sub-wavelength imaging and hyper-lens that are infeasible with natural materials. Moreover, hyperbolic metamaterials, being special kind of anisotropic metamaterial with dielectric tenor elements having the mixed signs, have attracted growing attention due to their ability to support very large wave vectors. As a consequence, the new types of surface waves are found. Contrarily, the introduction of MM/TCO interface leads to a transformation of the traditional-like SPPs. Surface waves of different kinds, including DSWs along with traditional-like SPPs, are examined. MM/dielectric and MM/TCO, is of the particular importance. The examination of two different interfaces, i.e. The propagation length of these DSWs is drastically limited by the penetration depth inside the lossy MM as it is caused by the specific damping capacity of metals. Especially, outstanding results take place if the metallic nanoelements are employed to the anisotropic structures, as it occurs, for example, with a simple metal-dielectric multilayer, a case where the angular range may surpass half of a right angle. The use of structured materials with extreme anisotropy provided a fertile background aiming to increase the range of directions of DSWs substantially, as it is compared with the rather narrow range observed with natural birefringent materials. In the latter case, a methodology developed by Tamm was adopted seeking to find a new type of surface wave, called as Dyakonov-Tamm wave, as it combines the features of Dyakonov surface waves (DSWs) and Tamm states. The process of replacement of the uniaxial medium by a biaxial crystal, an indefinite medium and a structurally chiral material may enforce the presence of hybrid surface waves with some parallel characteristics. Recently, it has been shown that by nanostructuring the metal surface, it is possible to modify the dispersion of SPPs or excite the SPPs in a prescribed manner. SPPs have promoted new applications in many fields such as microelectronics, photovoltaics, near-field sensing, laser technology, photonics, meta-materials design, high-order harmonics generation or charged particle acceleration. ![]() Coupling between photons and surface plasmon polaritons (SPPs) is enabled by the periodically nanostructured metallic films allowing for exceptional and tunable optical properties determined by a combination of design geometry, the surrounding dielectric permittivity and the choice of metal. Plasmonics and the recent birth of metamaterials (MMs) and transformation optics are currently opening a gateway to the development of a family of novel devices with unprecedented functionalities ranging from sub-wavelength plasmonic waveguides and optical nanoresonators to superlenses, hyperlenses and light concentrators. ![]()
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