Design of an electro-optical tunable race-track diamond microring resonator on lithium niobate

Abstract A diamond race-track microring resonator was designed on a lithium niobate/silicon substrate in the optical communication band by combining the unique optical properties of diamond with the electro-optical characteristics of lithium niobate. The single-mode conditions, propagation loss, and dispersion of the waveguide were systematically investigated. The key parameters of the microring resonator (with and without a race-track structure), such as radius and gap size, were calculated and optimized by the 2.5-dimension variational finite-difference time-domain method. The electro-optical tunable performance of the race-track microring resonator was simulated and analyzed. The effects of waveguide core layer thickness and electric field strength on the electro-optical effect were simulated and discussed. The tunable filter characteristics of the microring were also analyzed. The proposed work will help in manufacturing multi-functional and high-performance photonic integrated devices for optical communications and quantum optics.