Numerical simulation of metallic nanostructures interacting with electromagnetic fields using the Lorentz–Drude model and FDTD method

Abstract

In this paper, we present an analysis and modeling of the interaction of electromagnetic fields with metallic nanostructures using computational tools that allow us to study the phenomena that are produced as an electromagnetic field interacts with the nanostructure. The analysis of dielectric systems including metals can be very complicated because of the metal parameters. For this reason, we propose to integrate the dielectric function of the Lorentz-Drude model with the finite difference time-domain (FDTD) method, which will permit to study the surface and internal effects within the metal nanostructure system added to the dielectric system, and the interaction of electromagnetic fields with atoms, ions or molecules excited up to their resonant frequency, which causes transitions among atomic energy levels. We solved the system and showed the results of the simulation for the following case studies, silver nanosphere of 100[Formula: see text]nm in diameter, gold nanorod of 12[Formula: see text]nm in thickness and 30[Formula: see text]nm in length and gold nanogroove of 70[Formula: see text]nm.

Terahertz Nanoscopy of Metal and Gallium Implanted Silicon

“…17,18 A calculation method that adapts to the complex boundary conditions must be introduced. 14 Additionally, subwavelength resolution optical equipment is required to extract optical constants, such as scattering-type scanning near-field optical microscopy (s-SNOM) based on the THz-TDS setup. 19−21 Atomic force microscopy (AFM) probes produce strong electric field enhancement at the tip apex and radiate the near-field signal to the remote detector.…”

“…THz waves are sensitive to low-energy phenomena in bulk matter and molecules. These quantum phenomena can be simplified into classic oscillator models such as the Drude model , and Drude-Lorentz model …”

“…THz waves are sensitive to low-energy phenomena in bulk matter and molecules. These quantum phenomena can be simplified into classic oscillator models such as the Drude model 13,14 and Drude-Lorentz model. 15 Recent studies have found that the optical constants in the THz range are different, where a 3-order discrepancy between experimental and Drude model results was reported.…”

“…Recent studies have found that the optical constants in the THz range are different, where a 3-order discrepancy between experimental and Drude model results was reported . The size and shape of matter are vital at THz frequencies, since the free electron gas assumption is invalid, and we must analyze the inner electrical interaction. , A calculation method that adapts to the complex boundary conditions must be introduced . Additionally, subwavelength resolution optical equipment is required to extract optical constants, such as scattering-type scanning near-field optical microscopy (s-SNOM) based on the THz-TDS setup. − Atomic force microscopy (AFM) probes produce strong electric field enhancement at the tip apex and radiate the near-field signal to the remote detector. − Sub-10 nm imaging resolution was achieved. − …”

A new approximate analytical method and its convergence for nonlinear time-fractional partial differential equations

“…So, the theory of NFPDEs is a powerful theory to give a solution to engineering problems. See for example [1,2,3,4,5,6,7,8,9,10,11,12,13,14,15].…”