In this work, a two-dimensional photonic crystal ring resonator based temperature sensor is investigated. The device consists of a hexagonal array of air holes surrounded by the base material of germanium (Ge). The sensing mechanism is based on the shifting of transmission peak with refractive index changes in Ge induced by variation of temperature. Simulation results are obtained using finite difference time domain method (FDTD). The photonic band gap is studied by plane wave expansion method (PWE). The sensor has high sensitivity of 270 pm/K and high quality factor of 2028.86 with` wide range of temperature detection between 300 K to 800 K. The size of the structure is 112.91 (µm)2 and appropriate for sensing applications in nanotechnology.
