All-fiber cascade system for high-sensitive temperature monitoring: An exploration of the tunability of Ti3C2-MKRs

Abstract

A tunable all-fiber optical cascade temperature system is demonstrated with two microfiber knot resonators (MKRs) as sensing device (MKR_s) and reference device (MKR_r), respectively. The temperature monitoring device is prepared by depositing Ti3C2 onto MKR_s by optical deposition. Sufficient experimental evidence for temperature sensing sensitivity of the dual sensor device cascade system (MKR_r + Ti3C2-MKR_s) is 4.33 nm/°C, which is a 10.13-fold increase in sensitivity compared with the temperature sensing sensitivity of 0.427 nm/°C of the Ti3C2-MKR_s. After depositing Ti3C2 materials (∼400 μm) on the bare MKR_r, we further improve the sensitivity of the cascade system (Ti3C2-MKR × 2) to 9.20 nm/°C, which represents a significant 21.5 times improvement in sensitivity compared to Ti3C2-MKR_s. The sensitivity of cascade fiber optic sensors is controlled by varying the modified length of Ti3C2 materials optically deposited on the MKR_r surface. Overall, this study not only enhances device utilization but also provides a new research direction for the preparation of all-fiber sensors with tunable sensitivity.