Sensing Characteristics of a Three-Ring Grating Slit Micro Ring Resonator

Abstract

In this paper, a micro ring resonator with slit structure of three-ring grating is proposed to make the refractive index micro ring sensor have higher quality factor and sensitivity. Based on the traditional micro ring resonator, the structure adopts three micro rings and adds grating structure to the rings, which can realize the EIT-Like effect at different wavelengths. Furthermore, the quality factor and sensitivity of the micro ring resonator are improved. The structure is simulated using the finite difference time-domain (FDTD) technique and the influence of device parameters on the structure is investigated. Quality factor was found to be up to 24845, over threefold higher than conventional microring sensors. The sensitivity is 224.2nm/RIU, more than two times higher than the conventional micro ring refractive index.