A simple waveguide directional coupler is described which uses the split-block type of construction common in millimeter-wave components. The coupler uses an array of metal probes suspended on quartz stand-offs. Depending on the number of coupling elements, the coupling can be in the range 15-30 dB, with typically ± 2 dB variation across the waveguide band, and directivity > 10 dB. The coupler,...

We investigate the quantum entanglement between two quantum dots (QDs) in a plasmonic waveguide with a near-zero mode index, considering the dependence of concurrence on interdot distance, QD waveguide frequency detuning, and coupling strength ratio. High concurrence is achieved for a wide range of interdot distances due to the near-zero mode index, which largely relaxes the strict requirement ...

High reflectivity Bragg gratings have been written by ArF excimer laser through a phase mask into IOG-1 hybrid phosphate glass. After grating exposure, a waveguide was fabricated by silver-sodium ion-exchange. Reflectivities around 80% at a wavelength of ~ 1535 nm were measured from the waveguide for both quasi-TE and -TM polarizations. Waveguide laser operation with the photowritten waveguide ...

Nanoscale slot waveguides of hyperbolic metamaterials are proposed and demonstrated for achieving large optical field enhancement. The dependence of the enhanced electric field within the air slot on waveguide mode coupling and permittivity tensors of hyperbolic metamaterials is analyzed both numerically and analytically. Optical intensity in the metamaterial slot waveguide can be more than 25 ...

The finite-difference time-domain (FDTD) technique is applied in the calculation of the S-parameters of diode mounting and waveguide-probe structures. The influence of the critical geometrical design parameters on the coupling of the coplanar feedline probe to the waveguide is investigated. A waveguide absorber based on analytic Green’s functions is used to minimize the reflections over a wide ...

Let f be a number-theoretic function. A finite set X of natural numbers is called f -large if card(X) ≥ f(min(X)). Let PHf be the Paris Harrington statement where we replace the largeness condition by a corresponding f -largeness condition. We classify those functions f for which the statement PHf is independent of first order (Peano) arithmetic PA. If f is a fixed iteration of the binary lengt...

Micro and nanoscale mobile agents capable of self-propulsion in low Reynolds number fluids would have a great technological impact in many fields. Few known mechanisms are able to propel such devices. Here we describe helical nanobelt (HNB) swimmers actuated by an electric field-generated electro-osmotic force. These HNB swimmers are designed with a head and a tail, similar to natural micro-org...

This paper describes a new, compact, waveguide thermal isolator. The isolator is based on a recently developed microwave bandgap joint, a periodic structure which suppresses microwave fields propagating between two parallel conducting surfaces. When such a structure is placed between a pair of waveguide flanges, the flanges can be separated by a few percent of a wavelength before the leakage an...

Waveguide analysis is used to predict power levels received in a microcellular system in an urban environment. An Urban street with tall buildings on both sides is modeled by a plate parallel waveguide made of rough plates. The distribution of power among the waveguide modes tends to concentrate in the low order modes, at large distances from the source antenna. The waveguide–based model predic...

In this paper, the propagation properties of Surface Plasmon Polariton mode in Metal-Insulator-Metal waveguide are presented. An additional thin metallic film is inserted inside the insulator for higher confinement. Silver (Ag) has been taken as the metal and air, gallium lanthanum sulphide (GLS) and aluminum gallium arsenide (AlGaAS) as the insulators for the construction of the waveguide. Fin...