High-Sensitivity Silicon Few-Mode Microring Resonators for Temperature Sensing

High-sensitivity silicon few-mode microring resonators (MRRs) are proposed and designed for temperature sensing. The proposed structures consist of a single-mode bus waveguide and a multimode ring waveguide. According to the phase-matching condition, few-mode MRRs with three different radii are designed for the high-order TE1 mode operating. The large free spectral range (FSR) of 24.9 nm, 15.6 nm, and 7.76 nm are achieved at radii of 3, 5, and 10 mu m, respectively. For temperature sensing, high linear sensing sensitivity of 99 pm/k, 102 pm/k, and 100 pm/k can be obtained.