Here, we propose an optical filter and an optical power splitter based on two-dimensionalphotonic crystal all circular ring resonators. These structures are made of a square lattice ofsilicon rods with the refractive index n1=3.464 surrounded by air (with refractive indexn2=1). First, we have designed the filter and by using that, we designed a power splitter. Thetransmission efficiency and Quality factor for both, an optical filter and an optical powersplitter, respectively, are more than 90% and 1000. Resonant modes of the all-circular ringresonator with their corresponding degenerated poles and the transmission spectra arecalculated using the PWE, and 2D-FDTD methods respectively. Manuscript profile

In this paper, using annular resonator we have designed an adding and dropping filter light based ontwo-dimensional photonic crystals. The shape of ring resonator filter adding and dropping that wehave proposed is Race Track. This filter has a hexagonal lattice structure of silicon bars withrefractive index 3/46 that is located in the context of air with refractive index 1. Transmissionefficiency and quality coefficient of our proposed filter are respectively 94% and 310. Finite differencemethod in two-dimensional time domain (2-D FDTD) used for normalized transmission spectra ofphotonic crystal ring resonator and to calculate the photonic band, plane wave expansion method(PWE) has been used. Manuscript profile