Fast rf phase shifters may be needed, in powering a superconducting linac, between rf generators and accelerating cavities when one klystron feeds more than one cavity. The configuration with one klystron for many cavities needs orthogonal controls of magnitude and phase of rf power in order to preserve system performance while reducing construction cost. For this reason, a waveguide ferrite ph...

This paper describes the design and realization of a transition from a microstrip line to a ridge gap waveguide operating between 95 and 115 GHz. The study includes simulations, measurements, and a Monte Carlo analysis of the assembly tolerances. The purpose of this tolerance study is to identify the most critical misalignments that affect the circuit performance, and to provide guidelines abou...

The design and analysis of a dielectric guided-mode resonance filter (GMRF) utilizing a nonlinear material for the waveguide is presented. Small changes to the parameters of a GMRF have a large impact on its resonance. A nonlinear material can provide a small change in the refractive index of the waveguide, altering the resonance of the device and resulting in modulation of the transmitted and ...

We demonstrate design, fabrication, and characterization of two-dimensional photonic crystal (PhC) waveguides on a suspended silicon rich nitride (SRN) platform for applications at telecom wavelengths. Simulation results suggest that a 210 nm photonic band gap can be achieved in such PhC structures. We also developed a fabrication process to realize suspended PhC waveguides with a transmission ...

Incorporation of planar waveguide technology into a spectroelectrochemical sensor is described. In this sensor design, a potassium ion-exchanged BK7 glass waveguide was over-coated with a thin film of indium tin oxide (ITO) that served as an optically transparent electrode. A chemically selective film was spin-coated on top of the ITO film. The sensor supported five optical modes at 442 nm and ...

Transmission properties through sharp rectangular waveguide bends are investigated to determine the cut-off bending angles of the wave propagation. We show that a simple metallic diaphragm at the bending corner with properly devised sub-wavelength defect apertures of C-slits would be readily to turn on the transmissions with scarce reflections of the propagating modes, while preserving the inte...

We describe resonant excitation of a plasmon by the Gaussian-like leaky mode of an effectively single mode photonic crystal (PC) waveguide. Plasmon is phase matched by design with a waveguide mode, and travels in a metallic layer on the top of a PC waveguide. We observe that small changes in the ambient refractive index just outside the metal film lead to strong variations in the losses of a wa...

In this paper, we present the design and simulation of silicon-on-insulator (SOI) based integrated optic Directional Coupler. Planar waveguide devices based on SOI architecture offer attractive possibility of miniaturization because of the high difference in refractive index between Silicon and SiO2. It has been shown that this technology offers the ability to make devices with sharper bends wi...

Arrayed waveguide gratings are useful structures for the implementation of wavelength division multiplexing; however, in their current form, silica-based gratings are too large to be made cheaply or to use as an integrated component. This paper describes a Master of Engineering thesis which will attempt to design such a structure which is at least one order of magnitude smaller than the best on...

The design and performance of higher order mode (HOM) dampers for the SPEAR 2 RF system is presented. The SPEAR beam had experienced occasional periods of instability due to transverse oscillations which were driven by HOMs in the RF cavities. A substantial fraction of this RF energy was coupled out of the cavity into the waveguide connecting the cavity to the klystron. This waveguide was modif...