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Molecular fluorescence may strongly be affected by plasmonic environments, especially the ones with deep‐nanometer features, associated with the emergence of nonclassical effects. Such effects are largely investigated by a nonlocal hydrodynamic model with additional boundary conditions, describing the collective motion of the free electron gas in metals. The study of a fluorophore in the presence of the nano core–shell topology is performed, by employing the following models: the hard‐wall hydrodynamic model and the generalized nonlocal optical response. The analysis is conducted by investigating the fluorescence rates of the system, while considering the fluorophore located inside and outside the nanoparticle. It is demonstrated that the rates generated by the above models may considerably differ from the ones obtained via the classical approach. The optimal fluorescence enhancements for different size and material parameters are found both inside and outside the studied topology. [ABSTRACT FROM AUTHOR]

Metasurfaces that manipulate electromagnetic waves have gained significant attention in recent years. The focus has primarily been on planar devices, while many applications require curved surfaces. In this study, the authors propose an analysis approach for cylindrical cascaded (multilayer) metasurfaces. The approach combines the concept of sheet impedance in the spectral domain with a new transmission matrix formulation that is applicable to stratified, canonical curved geometries. Approximate formulas for the sheet impedance of common planar, metallic patterns are also adapted to curved geometries. The reported analysis approach allows one to determine the optimal spectral-domain, azimuthal dependence of a sheet impedance, as well as the best geometrical elements to obtain the required azimuthal variation. The results are verified through several cylindrical metsurface examples. [ABSTRACT FROM AUTHOR]

In this paper, a classical-type approach is used to analyze the hard horn antenna. The quasi-TEM mode in the longitudinally corrugated cylindrical waveguide is found by using the homogenized asymptotic boundary conditions. The finite horn length is accounted for by including a phase factor in the waveguide-aperture fields, and the radiation patterns are finally obtained by aperture integration. The bandwidth is found to be much wider than previously anticipated with respect to low cross-polarization. Also, an advanced mode-matching code has been used for verification of the aperture field and the radiation patterns obtained with the much faster classical model. © 2005 Wiley Periodicals, Inc. Microwave Opt Technol Lett 44: 516–523, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20684 [ABSTRACT FROM AUTHOR]

The mutual coupling between rectangular microstrip patches mounted on a spherical structure is studied in this paper. The analysis approach is based on the spectral-domain method of moments (MoM). An approximate method is developed to calculate coupling between currents located on different patches. A laboratory model is built to test different configurations of patches and to validate the calculated results. © 2004 Wiley Periodicals, Inc. Microwave Opt Technol Lett 40: 387–391, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.11389 [ABSTRACT FROM AUTHOR]

In this paper, the input impedance and radiation pattern of spherical rectangular patch antennas are studied. The electric field integral equation is numerically solved by applying the method of moments where the multilayer spherical structure is rigorously considered, using the spectral-domain algorithm for calculating Green's functions. In order to avoid numerical problems, a modified vector–Legendre transformation and normalized Legendre polynomials are defined and applied to the solution procedure. © 2003 Wiley Periodicals, Inc. Microwave Opt Technol Lett 36: 276–280, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.10741 [ABSTRACT FROM AUTHOR]

In this paper, the synthesis of a stacked patch antenna for circular polarization is presented. The antenna is analyzed by the full-wave approach based on the method of moments in the spectral domain. In order to find the optimal antenna parameters, a hybrid genetic algorithm that combines a global search of the common genetic algorithm and the efficiency of the direct search method is developed. The experimental results show SWR<2, with an axial ratio lower than 4 dB within 14% bandwidth. © 2001 John Wiley & Sons, Inc. Microwave Opt Technol Lett 31: 197–201, 2001. [ABSTRACT FROM AUTHOR]

We discuss the unidirectional current screen as an asymptotic strip boundary condition (ASBC) for analysis of field problems containing metal strip grids, and we introduce a related asymptotic corrugation boundary condition (ACBC) for analysis of corrugated surfaces. The boundary conditions are asymptotic in the sense that the exact boundary conditions approach the asymptotic ones when the strip and corrugation periods approach zero. © 1997 John Wiley & Sons, Inc. Microwave Opt Technol Lett 14: 99–101, 1997. [ABSTRACT FROM AUTHOR]