Domenico Pinto

Improved Complex-Envelope Alternating-Direction-Implicit Finite-Difference-Time-Domain Method for Photonic-Bandgap Cavities

In this paper, an improved complex-envelope alternating-direction-implicit finite-difference time-domain (CE-ADI-FDTD) method has been presented for the analysis of photonic-bandgap cavities. The improvement relies on a different approach of the perfectly matched-layer absorbing-boundary condition in order to avoid the formation of instability, as reported in the literature. The high numerical precision and efficiency obtained are clearly demonstrated through the agreement of the results obtained using CE-ADI-FDTD and their counterparts obtained using other rigorous approaches reported in the literature

Accurate Perfectly Matched Layer Finite-Volume Time-Domain Method for Photonic Bandgap Devices

In this letter, a new explicit time-domain method for the analysis of light propagation in photonic bandgap (PBG) devices is suggested. In essence, this method is based on the finite volume that employs triangular elements in order to accurately represent curved boundaries encountered in PBG devices. Moreover, uniaxial perfectly matched layer absorbing boundary conditions has also been incorporated to rigorously truncate the computational domain. The high numerical precision of the suggested approach is demonstrated through numerical examples.

Photonic crystals assisted slow wave structure for THz vacuum devices

A corrugated waveguide with Photonic Crystal (PhC) wall is proposed for effective beam-wave interaction with wide sheet beams at terahertz frequency. Compared to conventional corrugated waveguides, PhC technology provides efficient field confinement in a naturally open structure which allows for improved level of vacuum pumping alleviating the typical assembling issues.

Analysis of Nitrides- and TCOs-Based Plasmonic Waveguides for Slow-Wave and Negative Index Sub-Wavelength Propagation

In this paper, a comparison between metal-insulator-metal (MIM) waveguides made of silver and newly emerging plasmonic materials is reported. In particular, titanium nitride (TiN) from the class of nitrides, and gallium zinc oxide (GZO) from the class of transparent conducting oxides, are proposed as alternatives to conventional metals for the more flexible exploitation of plasmonic properties. Depending on the specific application, the new choices of the plasmonic material allow for tuning of the surface plasmon resonance and may also reduce typical conductive losses. Moreover, compared to noble metals, these new plasmonic materials have the extremely important property of being compatible with the mature CMOS technology. In this paper, the specific application of MIM waveguides made of TiN and GZO for dispersion engineering (slow-wave propagation and negative effective index) is considered for the first time.

Accurate Analysis of Plasmonic Devices With a New Drude Two Critical Points MRTD Method

A new Drude two critical points (D-2CP) multiresolution time domain numerical method for the simulation of surface plasmon polariton in metallic inclusions is presented. A D-2CP model is used to accurately describe the dielectric function of the metallic inclusions, and it is compared with other Drude models reported in the literature. The superior accuracy given by the D-2CP model avoids the formation of spurious reflections at the boundary interface between metal and dielectric, which can greatly affect the accuracy of the numerical results.

New Alternating-Direction-Implicit Finite-Difference-Time-Domain Method for Photonic Crystal Devices

In this paper, a new alternating direction implicit finite difference time domain (ADI-FDTD) method has been presented. The method relies on a more stable formulation of the perfectly matched layer (PML) absorbing boundary condition making it suitable for the simulation of photonic crystals (PhCs) based devices. Its accuracy and efficiency are demonstrated by numerical examples which are shown to be in excellent agreement with those reported in literature.