Presented is a review of recent work by the authors in which the lowestorder transverse-electric (TE1) mode of a parallel-plate waveguide (PPWG) is used for terahertz (THz) applications. This work adds a new dimension to the multitude of diverse THz applications made possible by PPWGs. Using the TE1 mode, demonstration is presented of an ultra-low loss THz waveguide, a highly sensitive microflu...

We design a novel long-range hybrid wedge plasmonic (LRHWP) waveguide composed of two identical dielectric nanowires symmetrically placed on two opposed wedges of a diamond shaped metal wire. With strong coupling between the dielectric nanowire mode and long-range surface plasmon polariton (SPP) mode, both deep subwavelength mode confinement and low propagation loss are achieved. On one hand, w...

Abstract: Alteration of a geometry parameter in the cross section of a dielectric waveguide with piecewise constant permittivity profile can be regarded as a refractive index perturbation in a layer along a dielectric discontinuity line. Starting from these thin layer perturbations, we derive explicit expressions for partial derivatives of propagation constants with respect to the transverse wa...

Research on two-dimensional designer optical structures, or metasurfaces, has mainly focused on controlling the wavefronts of light propagating in free space. Here, we show that gradient metasurface structures consisting of phased arrays of plasmonic or dielectric nanoantennas can be used to control guided waves via strong optical scattering at subwavelength intervals. Based on this design prin...

Wave propagation is a ubiquitous concept throughout physics. When the aim is to focus a wave at a given point in space or time, the resolution that can be achieved is usually limited by diffraction. However, time reversal is a method which takes advantage of multipath elements in a given channel and uses them to obtain resolution beyond the diffraction limit. This is known as super-resolution. ...

Loss compensation in long-range dielectric-loaded surface plasmon-polariton waveguides is theoretically analyzed when rare-earth-doped double tungstate crystalline material is used as the gain medium in three different waveguide configurations. We study the effect of waveguide geometry on loss compensation at the telecom wavelength of 1.55 μm, and demonstrate that a material gain as small as 12...

In this paper we review basic properties of coupled periodic and aperiodic nanopillar waveguides. A coupled nanopillar waveguide consists of several rows of periodically or aperiodically placed dielectric rods (pillars). In such a waveguide, light confinement is due to the total internal reflection, while guided modes dispersion is strongly affected by the waveguide structure. We present a syst...

We investigate the properties of the modes supported by three-dimensional subwavelength plasmonic slot waveguides. We show that the fundamental mode supported by a symmetric plasmonic slot waveguide, composed of a subwavelength slot in a thin metallic film embedded in an infinite homogeneous dielectric, is always a bound mode. Its modal fields are highly confined over a wavelength range extendi...

A novel spectral method with variable transformation, the adaptive Hermite-Gauss decomposition method (A-HGDM), has been developed and applied to the analysis of three-dimensional (3D) dielectric structures. The proposed method includes an optimization strategy to automatically find the quasi-optimum numerical parameters of the variable transformation with low computational effort. The techniqu...

The Dielectric Resonator Antenna (DRA) is one of the efficient radiator which is used to achieve broadband and cost effective communication in wireless technology. The Substrate Integrated Waveguide (SIW) technology is the most assuring structure for implementation of circuits and components for millimeter wave and microwave applications. A design approach to improve the impedance bandwidth of ...