Low Temperature Sensor Based on One-Dimensional Photonic Crystals

Based on the Green function method and by taking account of the thermal expansion effect and thermo optical effects, we theoretically investigates the transmittance spectra of a one dimensional photonic crystal (PC) with two defects layers designed as (AB)(CBC)-C-6(BA)(6) made of Silicon dioxide (SiO2), Titanium dioxide (TiO2), and Bi4Ge3O12 (BGO). Numerical results show that the defect mode shifts toward the low frequencies region as the temperature of the structure increases and the central wavelength of defect modes changes linearly with temperature. The proposed structure may be used as a low temperature sensor.