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....

The add/drop wavelength filter is an essential component in the new-generation photonic network. Microring resonator filters using high index contrast (HIC) optical waveguides are recently attracting attention as add/drop filters owing to their compactness, functionality such as dispersion compensation, and ease of filter synthesis. In particular, the vertically coupled microring resonator (VCM...

We demonstrate an all-fiber add-drop filter composed of a microfiber knot (working as a resonator) and a fiber taper (working as a dropping fiber). The dropping taper can be either parallel or perpendicular to the input port of the filter. A quality factor (Q factor) of 13,000 is obtained from a parallel-coupling 308 microm diameter microknot add-drop filter with a free spectral range (FSR) of ...

In This paper, optical Filter based on photonic crystal ring resonator with square lattice is proposed. The add-drop filter is designed by coupling in line quasi waveguide and resonant cavity. Photonic band gap is obtained by plane wave expansion method (PWE) and Simulation is carried out by Finite Difference Time Domain method (FDTD).This type of add-drop filter provide high transmission effic...

In this paper, effects of the structural parameters on the optical characteristics of an add-drop filter, consisting of two straight waveguides and a micro-ring resonator (MRR), have been investigated. In this research, effects of MRR radius, the width of MRR and waveguide and the gap between MRR and waveguide, on free spectral range (FSR) and coupling coefficient have been studied. It is found...