We study the effect of confinement on surface plasmons in a planar cavity with a wall coated with a lossy metal as well as with two walls coated with a lossy metal. The dispersion curves are studied in details and explicit relations are obtained locally for the first case. It is shown that modes strongly concentrated at the air-metal interface can be obtained. Finally, we discuss the modes of the lossy waveguide, in particular their completeness.

We, theoretically, show that it is possible to realize the strong coupling of a guided mode with a surface plasmon in a waveguide coated by a lossy metal. The dispersion relation of such a structure is obtained through the T-matrix algorithm combined with the the Cauchy integral technic that allows for rigorous computations of the complex poles. The strong coupling is identified by the anticrossing in the dispersion diagram and simultaneously by the crossing in the loss diagram (circular frequency vs. the imaginary part of the wave vector). The spatial structures of the different modes (original and hybridized) are computed and it is shown that spatial Rbbi oscillations appears for one of them. This last feature can be exploited to reduce losses in the propagation of surface plasmons.

Light transport in two-dimensional disordered metamaterials made of high-permittivity rods is studied theoretically. Different regimes of transport are observed and explained in terms of coupled electric and magnetic dipolar resonances. A very general homogenization theory is derived. Light propagation at frequencies close to the magnetic dipole resonance is investigated at the microscopic level and is shown to rely on hybrid, necklace-like, states. The stability of these results versus the permittivity and disorder are investigated.

The Modal Method by Gegenbauer polynomials Expan- sion (MMGE) has been recently introduced for lamellar gratings by Edee [8]. This method shows a promising potential of outstanding convergence but still suffers from instabilities when the number of polynomials is increased. In this work, we identify the origin of these instabilities and propose a way to remove them.

The homogenization of arrays of metallic rods was studied. Using standard homogenization theory, the effective permittivity was obtained. The onset of resonances was evidenced and showned to be linked with the negative sign of the real part of the permittivity. Numerical computations were performed to test the homogeneous model.

We employ a time-domain method to compute the near field on a contour enclosing infinitely long cylinders of arbitrary cross section and constitution. We therefore recover the cylindrical Hankel coefficients of the expansion of the field outside the circumscribed circle of the structure. The recovered coefficients enable the wideband analysis of complex systems, e. g., the determination of the radar cross section becomes straightforward. The prescription for constructing such a numerical tool is provided in great detail. The method is validated by computing the scattering coefficients for a homogeneous circular cylinder illuminated by a plane wave, a problem for which an analytical solution exists. Finally, some radiation properties of an optical antenna are examined by employing the proposed technique.

The strong coupling between a mode confined in a dielectric waveguide and a surface plasmon was demonstrated. It was shown that the strong and weak coupling regime can coexist. The strong coupling allows the spatial exchange of energy and opens a way towards the quantum control of plasmon, i.e. quantum plasmonics. © (2011) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.