Simultaneous measurement of temperature and relative humidity based on a twisted microfiber coated with nanomaterials

We propose a twisted microfiber interferometer sensor coated with boron nitride (BN) nanosheets for simultaneous measurement of relative humidity (RH) and temperature ( T ). Sensitive material characteristics (BN nanosheets) enhance refractive index (RI) sensing sensitivity of proposed devices. A twisting process on the microfiber surely improves the evanescent field interaction with the deposited layer. The experimental results show that the RH sensitivities are − 121.6 p m / % R H and 0.26 dBm/%RH for humidity range from 46% to 72% and T sensitivities of 23.5 pm/°C and − 0.045 d B m / ∘ C from 50°C to 90°C. The twisted microfiber interferometer has the advantages of compact structure, high sensitivity, and multiparameter measurement, which has certain potential for more applications.