A generalized auxiliary differential equation (ADE) finite-difference time-domain (FDTD) dispersive scheme is introduced for the rigorous simulation of wave propagation in metallic structures at optical frequencies, where material dispersion is described via an arbitrary number of Drude and critical point terms. The implementation of an efficient perfectly matched layer for the termination of such media is also discussed and demonstrated. The model's validity is directly compared with both analytical and numerical results that employ known dispersion schemes, for the case of two benchmark examples, transmission through a thin metal film and scattering from a metallic nanocylinder. Furthermore, the accuracy of the proposed method is also demonstrated in the study of the optical properties of Ag and Au metal-insulator-metal waveguides, filters, and resonators, which also involve dielectrics whose material dispersion is described by the Sellmeier model.

A fourth-order accurate in space and second-order accurate in time, Finite-Difference Time-Domain (FDTD) scheme for wave propagation in lossy dispersive media is presented. The formulation of Maxwe...

This letter addresses the stability problem of two auxiliary differential equation (ADE) finite-difference time-domain (FDTD) methods for the case of modified Lorentz media, using the combination of the von Neumann method and the Routh-Hurwitz criterion. A rigorous investigation supported by FDTD simulations designates that the stability criterion of the conventional FDTD method can be preserved via the proper selection of the difference and averaging operators. A set of conditions for the dispersive medium parameters is derived, providing the stability limit for both FDTD schemes with practical guidelines for evaluating the fitting of experimentally studied materials.

A finite-difference time-domain (FDTD)(2,4) scheme with second-order accuracy in time and fourth-order accuracy in space for the precise solution of Maxwell's equations in lossy dielectrics is presented. Compared with the ordinary FDTD method the novel technique reduces lattice reflection errors, increases the overall accuracy and provides significant computational savings. Numerical results for a waveguide problem indicate the efficiency and robustness of the proposed formulation.

A site-specific numerical model, based on the finite-difference time-domain method, is developed in this paper for the indoor radio channel. The scenario of interest is concerned with wave propagation in a typical office environment, for which several simulations are performed considering different placements of the transmitting antenna. Both the 2- and 5-GHz bands are examined, where contemporary wireless local area networks operate. Important channel characteristics are evaluated via the estimation of received power levels, as well as the examination of small-scale fading and time dispersion