Chloroform infiltrate temperature sensor using asymmetric circular dual-core photonic crystal fiber

Abstract

A new temperature sensor based on asymmetry in dual circular core photonic crystal fiber (ADCPCF) is proposed where both the cores infiltrate by chloroform. To analyze the temperature dependent propagation characteristics, the thermo-optic coefficient of chloroform and silica is used. The asymmetry of the dual-core is confirmed by using the core radius of 1.615 and 1.45 µm, respectively. In the proposed design, the essential optical properties such as effective refractive index difference (birefringence), coupling length, and transmission spectra are determined by employing the finite element method (FEM) with the perfectly matched layer (PML). The effective refractive index of the chloroform varies with temperature within a certain range. Moreover, with the increase of every 1 °C temperature the effective index difference enhances to almost 4%. Also, with the reduction of every 100 nm wavelength the birefringence decrease to 0.125×10 -3 and 0.092×10 -3 for 35 and 30 °C temperature, respectively. The Numeric analysis shows the maximum sensitivity of 49.80 nm/°C at 1.61 mm fiber length for 2.9 µm lattice pitch with 2.25 µm air-hole diameter. Furthermore, every 1 °C temperature increment, the proposed ADCPCF exhibits approximately 16% increases of sensitivity than the existing result. In addition, the proposed ADCPCF reveals that the guiding properties like coupling length, birefringence, and transmission spectra are wavelength and temperature reliance.