A refractive index sensor composed of two straight metal-insulator-metal waveguides and a ring resonator is presented. One end of each straight waveguide is sealed and the other end acts as port. The transmission spectrum and magnetic field distribution of this sensor structure are simulated using finite-difference time-domain method (FDTD). The results show that an asymmetric line shape is obs...

A compact (1.2 mm2) fully integrated mid-IR spectrometer operating in the 3 μm wavelength range is presented. To our knowledge this is the longest wavelength integrated spectrometer operating in the important wavelength window for spectroscopy of organic compounds. The spectrometer is based on a silicon-on-insulator arrayed waveguide grating filter. An array of InAs0.91Sb<...

A compact tunable dual-band bandpass filter (BPF) based on substrate integrated waveguide (SIW) and defected ground structure (DGS) is investigated in this paper. The second passband can be flexibly controlled by changing the dimensions of the updown DGSs whereas the first passband is fixed. The proposed filter exhibits improved selectivity due to the introduction of four left-right DGSs genera...

We have developed a sound synthesis algorithm for the harpsichord by applying the principles of digital waveguide modeling. A short overview on the acoustics of the harpsichord is given, and signal-processing techniques for synthesizing harpsichord tones are suggested. In particular, a new loop filter for the digital waveguide model is introduced and analyzed. The implementation of the synthesi...

In this paper, we present a novel broadband bandpass filter based on spoof surface plasmon polaritons (SSPPs) in the microwave frequency band. The proposed bandpass filter includes three parts: (1) coplanar waveguide (CPW); (2) matching transition; and (3) coupled structure that is an asymmetric coupled filter constructed by five grooved strips. The proposed bandpass filter realizes excellent l...

Circular and Radial SIW cavity resonators are proposed to enhance the performance of SIW bandstop filter. Prior to this research work, rectangular cavity resonator was used to produce bandstop response. The design of the circular and radial SIW bandstop filters are done by directly coupling circular and radial cavity resonators to the SIW line. The SIW bandstop filters are designed to operate a...

Hexagonal dual-mode cavity and its application to substrate integrated waveguide (SIW) filter are presented. The hexagonal SIW resonator which can combine flexibility of rectangular cavity and performance of circular cavity is convenient for dual-mode bandpass filters design. By introducing coupling between source and load, the filter not only has good selectivity due to two controllable transm...

Utilizing the small bending radius of high index contrast optical waveguides, ultra-compact optical devices such as waveguide branch, Mach-Zehnder interferometer, arrayed waveguide grating filter, microring resonator filter, and so on can be realized. We have proposed and demonstrated a vertically coupled microring resonator as an Add/Drop filter, and recently realized a hitless wavelength chan...

In this paper, the forward and backward propagating modes in an optical waveguide structure namely the fiber Bragg filter also considered as a one dimensional photonic crystal, is analytically computed as a function of grating length for coupled optical modes. AlxGa1xN/GaN material composition is considered as a unit block of the periodic organization, and refractive index of AlxGa1-xN/GaN is t...

Transmission of intense femtosecond 825 nm pulses progressively produces a waveguide at the entrance of a heavily Ge-doped silicate fiber. The waveguide behaves as a multimillimeter long-fiber bandpass filter that scatters away light with wavelengths shorter or longer than 850 nm. This phenomenon has been correlated with the ~800 nm photosensitivity producing type I-IR fiber Bragg gratings in s...