a compact and sharp-rejection ultra-wideband (uwb) microstrip band-pass filter (bpf) is developed using of left handed metamaterials realized by complementary split ring resonator (csrr). moreover, proposed structure consists of two doublets parallel coupling gaps at each side of a microstrip ring. in comparison with some other filters, this structure shows a significantly wider passband due to...

require high-fi nesse, high-quality factor (highQ ) micro-lasers. Such lasers must be exceptionally transparent at their emission wavelength. But if highQ micro lasers exhibit correspondingly weak absorption at the pump wavelengths, they are challenging to excite. Here, we demonstrate micro-ring lasers that exhibit Q > 5.2 × 10 6 and a fi nesse of > 1.8 × 10 4 with a direct-illumination, non-re...

We introduce a fiber ring optical resonator based on adiabatic fused-fiber grating couplers. The coupling of a through fiber to the resonator is controlled by the strength of the fiber Bragg gratings. By using two of these couplers and incorporating erbium-doped (ED) fiber in the ring, we control the internal loss of the ring by pumping the ED fiber. The transmission spectra of the through port...

Here, we propose an add-drop and a channel drop filter based on two-dimensional photonic crystal all circular ring resonators. These structures are made of a square lattice of silicon rods with the refractive index n1=3.464 surrounded by air (with refractive index n2=1). The broadest photonic band gap occurs at the filling ratio of r/a = 0.17. Two linear defect W1 waveguides couple to the ring....

Ring resonator optical switches using electro-optic materials have been proposed. The propagation loss of the waveguides and the resonance characteristics of ring resonators with different refractive indices are simulated. The operation voltage is estimated based on the results of the simulations and is found to be 0.70V in the case of the ring resonator switch with a K(Ta, Nb)O3 core and KH2PO...

This investigation proposes the use of molecular network topology for drug delivery and diagnosis network design. Three modules of molecular network topologies, such as bus, star, and ring networks, are designed and manipulated based on a micro- and nanoring resonator system. The transportation of the trapping molecules by light in the network is described and the theoretical background is revi...

We show a diffraction-based coupling scheme that allows a micro-resonator to directly manipulate a free-space optical beam at normal incidence. We demonstrate a high-Q micro-gear resonator with a 1.57-um radius whose vertical transmission and reflection change 40% over a wavelength range of only 0.3 nm. Without the need to be attached to a waveguide, a dense 2D array of such resonators can be i...

The frequency resolution of an active waveguide ring resonator spectrometer is fundamentally limited by spontaneous emission noise produced by the gain medium. A closed-form expression for this resolution is derived, and the result is used to determine the minimum, rms, angular rotation rate, random walk error achievable by an active ring resonator gyroscope. An active waveguide ring resonator ...

The highly efficient coupling of light from conventional optical components to mode volumes lies in the heart chip-based micro-devices, which is determined by mode-matching between propagation constants fiber taper and whispering-gallery-mode (WGM) resonator. Optical gyroscopes, typically realized as fiber-optic gyroscopes ring-laser have been mainstay diverse applications such positioning iner...

Optical structures fabricated on silicon-on-insulator technology provide a convenient platform for the implementation of highly compact, versatile and low cost devices. In this work, we demonstrate the promise of this technology for integrated low power and low cost optical gas sensing. A room temperature ethanol vapor sensor is demonstrated using a ZnO nanoparticle film as a coating on an SOI ...