Si-SiO2 Clustery Random Photonic Crystal Based Thermo-Optic Sensor

This paper highlights the temperature sensing behavior of the 4-Cmax clustery disordered structures. The disordered structure can be obtained by grouping the higher refractive index layers to the maximum of 4 cluster sizes, randomly distributing these groups among the layers with the lower index of refraction. The sensor has been realized using silicon (Si) and silicon dioxide (SiO 2 ) materials. The silicon refractive index is highly dependent on the temperature; whereas the silicon dioxide has enough temperature stability. The transmission spectra of the 1D photonic structure is numerically calculated using the transfer matrix method. The thermo-optic responses of the desired sensors were measured within the temperature range of 25 to 200 °C. It is worth noting that the 4-Cmax clustery structures can sense the temperature in both the magnitude and wavelength of the transmittance peaks. Hence, the performance of the sensor can be improved by combining the sensitivity of both scalar quantities. The maximum sensitivity at the best operating temperature range (100-125 °C) was found to be 1.3824 × 10 − 4 nm/°C 2 . The proposed sensor shows linearity of about 0.999 R 2 value.