An idler light power measurement temperature sensor based on the four-wave mixing in a highly nonlinear fiber

In this study, an idler light power measurement temperature sensor based on four-wave mixing (FWM) is designed and analyzed experimentally. In the experiments, the FWM effect is realized in a highly nonlinear fiber (HNLF). The FWM conversion efficiency of the proposed sensor is calculated, and its temperature sensing is evaluated by changing the pump wavelengths and the signal light powers. Unlike previous studies on the FWM temperature sensors, this work uses the idler light power as sensing basis. The experimental results show that the output power of the idler light varies significantly with the temperature at different pump wavelengths. In the experiment, a temperature sensor with a measurement range from 20 degrees C to 80 degrees C is used. The results show that at a wavelength of 1540 nm, the average signal light power is 60 mW, and the proposed sensor's sensitivity is 0.1295 dB/degrees C. The proposed sensor is easy to operate and allows performing measurements conveniently. In addition, it provides an improved measuring method for FWM-based temperature sensing.