薄膜铌酸锂微环高精度微波光子温度传感器OA

This paper presents a high-precision temperature sensor based on a high-quality factor thin-film lithium niobate microring resonator integrated with a microwave photonic readout system.The microring res-onator,with a narrow linewidth of 2.87 pm and a high Q-factor of 105,functions simultaneously as the tem-perature-sensing element and the core signal processing component of a microwave photonic filter.Through the thermo-optic effect,temperature variations are converted into shifts in the optical resonance wavelength,which are innovatively mapped to linear changes in the passband center frequency of the microwave photon-ic filter.A vector network analyzer is employed to accurately detect the microwave frequency response,en-abling temperature measurement via high-resolution frequency variations and establishing a quantitative model between temperature and frequency shift.In contrast to conventional methods that directly detect op-tical wavelength shifts,the proposed microwave photonic readout technique linearly converts minute reson-ance wavelength shifts into changes in the microwave center frequency,thereby overcoming the resolution limitations inherent in conventional optical spectrum analyzers.Experimental results demonstrate a sensitiv-ity of 27 MHz/℃ and a resolution of 0.002 ℃,with excellent linearity maintained under temperature vari-ations as small as 0.01 ℃.This work effectively resolves the trade-off between sensitivity and resolution in traditional optical temperature sensing,offering a novel solution for on-chip integrated high-precision tem-perature monitoring.