Nmmerical Study On Sengsing Properties Of Optical Ring Resonator

Due to the high sensitivity and fast response of optical ring resonator sensor, it has widely application in biological and chemical detections. It can be used to detect proteins, virus, poison gas, and TNT molecules and so on. Optical ring resonator with characteristic of high Q factor, the interaction of light with matters can be enhanced obviously, then improving the sensitivity of devices. An optical-ring-resonator-based sensor has a high sensitivity, so it is good for making high sensitivity and low detection sensor devices. This paper focused on the properties of optical microring resonator, it carries out Q factor and sensitivity enhancement and detection limit reduction of the optical ring resonator sensor. The main contents are as follows:(1)Adopting effective index method, waveguide mode was analyzed in detail, and the single-mode transmission conditions of the straight waveguide were calculated. And using optical coupling mode theory, the relationship between waveguide gap and coupling coefficient of the silicon-based racetrack resonator was further studied, and the structure parameters of the optical racetrack resonator impacting on Q values in1.55μm wavelength was discussed. Simulation results show that Q values up to105at waveguide loss of0.2dB/cm.(2)The sensitivity of asymmetric optical ring resonator sensor was theoretical analyzed, using the method of light intensity with the effective refractive index changes, the main factors which influence the sensitivity are: transmission factor σ, the coupling factor t, the waveguide spacing and maximum sensitivity S3m corresponding relation was established(3)Adjusting the light transmission coefficient in the ring, the coupling coefficient and the coupling length between the ring and the straight waveguide, the limit detection of racetrack resonator was studied, and the effects of those parameters on the structure of the detection limit were simulated and analyzed. Selecting the appropriate structure parameters, the structure of the detection limit was achieved to10-7RIU, providing theoretical support for the preparation of an optical ring resonator in the process.