Periodic dielectric materials offer a great deal of control over the propagation of light.1 Usually the basic idea is to design periodic dielectric structures that have a band gap for a particular frequency range. In a recent study2 Meade et al. showed that defects in a three-dimensional (3-D) periodic dielectric material (photonic crystal) can admit localized states within a band gap. It is th...

We introduce a plasmonic waveguide system, which supports a subwavelength broadband slow-light guided mode with a tunable slowdown factor at a given wavelength. The system consists of a metal-dielectric-metal (MDM) waveguide side-coupled to a periodic array of MDM stub resonators. The slowdown factor at a given wavelength can be tuned by adjusting the geometrical parameters of the system. In ad...

The rectangular dielectric waveguide (RDWG) technique has been previously described for the determination of complex permittivity of a wide class of dielectric materials of various thicknesses and cross sections. This paper presents a unified RDWG technique for the determination of the dielectric constant of materials. Some measurement results are reported in the W -band frequencies to demonstr...

where is the angular frequency and F/m is the dielectric constant c of vacuum. The contribution of the bulk conductivity ( ) have been here separated to any other sort of losses ( ). The problem of the electromagnetic scattering due to a dielectric slab is briefly introduced. To this aim the model shown in Fig. 1 is considered: a unit amplitude wave is incident on a dielectric slab of thick...

Proof of concept of a cavity backed slot antenna based on inverted microstrip gap ‎waveguide (IMGW) technology is presented. Since the antenna is operating based on the ‎first resonating mode of the cavity, it is more compact compared to the ordinary cavity ‎backed slot antennas in which the second cavity mode is used for radiation. Furthermore, ‎the proposed antenna element introduces lower lo...

We have modeled and numerically simulated the performance of a dielectric-loaded graphene surface-plasmon-polariton (DL-GSPP) waveguide as a biochemical sensing device. In our device, the conventionally used gold layer is replaced with a graphene microribbon for the detection of biochemical molecules. The graphene layer is incorporated to minimize ohmic losses and to enhance the adsorption of b...

Introduction Traveling waves inside a bore of a scanner can propagate as RF modes of cylindrical or coaxial waveguides. The traveling-wave (TW) concept may offer large FOV [1], new encoding mechanisms [1-3], and more comfortable environment for patients. Since MR scanners have cylindrical symmetry, the waveguides are ideally suited for far-field traveling waves MR experiments. For MR scanners, ...

The design and validation of a dual polarization source for waveguide-coupled millimeter and sub-millimeter wave cryogenic sensors is presented. The thermal source is a waveguide mounted absorbing conical dielectric taper. The absorber is thermally isolated with a kinematic suspension that allows the guide to be heat sunk to the lowest bath temperature of the cryogenic system. This approach ena...