Two-mode microring resonator with an embedded periodic hole array for temperature sensing

Silicon-based microring resonators (MRRs) have shown great potential for on-chip temperature-sensing applications. In this paper, we propose and demonstrate a silicon two-mode microring resonator (TM-MRR) with an embedded periodic hole array for temperature sensing. A temperature sensitivity improvement of at least 25% is achieved in the single-ring MRR by exploiting the periodic hole array to support both TE 0 and TE 1 modes. The optimized design of the proposed temperature sensor has a ring-waveguide width of 0.84 µm and an inner diameter of only 10 µm. Experimental results indicate a temperature sensitivity of 109.41 pm/°C and an extinction ratio of 17.276 dB. The proposed sensor achieves high sensitivity with a compact size, offering a feasible solution for integrated high-precision sensing applications.