▎ 摘 要
Mid-infrared (mid-IR) microring resonators (MRRs) have been extensively studied for biochemical sensing. However, the temperature fluctuation is an undesirable cross-sensitive effect for refractive index (RI) sensing. Here, we study an electric-field-assisted resonance scanning (EARS) spectroscopic technique based on a graphene-on-silicon dual-mode MRR to overcome this limitation. Specifically, based on the proposed method, we theoretically achieved a RI measuring error of only 2% under a temperature fluctuation of 1K, which is improved by a factor of ten compared with a single-mode MRR. Moreover, a single-wavelength mid-IR laser is utilized in the technique, significantly simplifying the characterization setup. Also, we discuss the limit of detection and range of measurement of the EARS technique. Our study paves a promising way of developing monolithically chip-integrated mid-IR sensing devices. (C) 2021 Optical Society of America