Metallic nanoparticles play an important role in the design of sensing platforms. In this paper, a new electromagnetic study for conical metal nanoparticles, working in the Near Infrared and Visible frequency regime, is proposed. The structures consist of inclusions, arranged in an array configuration, embedded in a dielectric environment. The aim of this work is to develop new analytical models, in order to describe the nanoparticles electromagnetic behavior in terms of extinction cross-section (absorption and scattering). The closed-form formulas link the conical nanoparticles geometrical and electromagnetic parameters to their resonant frequency properties in terms of wavelength position, magnitude and bandwidth. The proposed models are compared to the numerical results and to the experimental ones, reported in literature. Good agreement is obtained. The proposed analytical formulas represent useful tools for sensing applications. For this reason, exploiting such models a new sensing platform able to detect different blood diseases is obtained. Numerical results confirm the capability of the proposed structure to be used as a sensing platform for medical diagnostics.

Abstract-In this contribution we propose a numerical investigation of a new type of nanoshell particles. The structure consists of a core/shell particle with a PMMA (PolyMethyl MethAcrylate)-Graphene core and Au thin shell. The proposed particles exhibit a strong near electric field intensification when an electromagnetic plane wave in the Visible regime is applied. The optical properties are evaluated and discussed in terms of resonant behavior and the near electric field distribution. Finally, the sensitivity performance of the structure is analyzed for biosensing applications.

In this paper we propose a new approach to study the electromagnetic field in Surface Plasmon Resonance (SPR) meta-structures. The geometry is a planar structure infinitely extended with a pulse excitation current embedded in the substrate. The general solution has been applied to a specific geometry that is frequently employed to model practical problems. The minimization of the thickness changes spectral Green's function in a more efficient form, suitable for calculations. Plasmon electric field expression on interface plane is obtained. This kind of meta-structures is suitable in various fields of application (e.g. optoelectronics and electromagnetic sensors).

No abstract