Design of High Sensitive Pressure and Temperature Sensor Using Photonic Crystal Fiber for Downhole Application

Permanent monitoring of two important parameters, pressure and temperature, plays an important role in reservoir engineering to increase the production rates of oil wells. The numerous advantages of photonic crystal fiber (PCF) sensors make them a proper choice as a sensor in the hostile environment of well. In this paper, we propose short length, high sensitive pressure, and temperature sensor based on hollow-core PCF. The validation of the proposed design is carried out by employing the 3-D finite-difference time domain (FDTD) method. Our sensor mechanism is based on the transmission peak wavelength shift caused by the temperature/pressure changes, with special emphasis on geometric parameters of the structure of PCF. We show that the proposed design provides a sensitivity about 480 nm/RIU with a linear dependence of the resonance wavelength on the refractive index of the ambient and PCF holes at $\lambda = 1.55 \mu\hbox {m}$ .