Dual-mode optical thermometers and optical fiber temperature sensor based on La2MoO6: Er3+, Yb3+ phosphors

For the first time, a straightforward optical fiber temperature sensing system based on La 2 MoO 6 :Er 3+ , Yb 3+ phosphors is proposed. The La 2 MoO 6 : Er 3+ , Yb 3+ phosphors were synthesized successfully using the molten salt method. A dual-mode temperature measurement technique based on the fluorescence intensity ratio (FIR) is introduced. The thermally coupled energy levels ( 2 H 11/2 and 4 S 3/2 ) and non-thermally coupled levels ( 2 H 11/2 and 4 F 9/2 ) exhibit maximum relative sensitivities of 1.24 % K −1 and 0.79 % K −1 at 293 K, respectively. The temperature resolution achieved was below 0.5 K. By utilizing the phosphor and optical fiber temperature sensor , real-time and accurate temperature monitoring was achieved, with a temperature deviation of less than 0.5 K. The optical fiber temperature sensor system provides exceptional reversibility and stability, while also playing a crucial role in precise remote temperature measurements under challenging conditions.