Design and analysis of the pressure sensor based on 2D photonic crystal consisting of micro-cavity

In this paper we design and analyze a photonic crystal (PhC) based pressure sensor. 2D hexagonal lattice having infinitely long circular silicon rods of refractive index 3.5 in air background has been considered here. There are two photonic crystal waveguides (PCWs) and a micro cavity in between in the design. The micro-cavity offers maximum coupling between two PCWs at resonant wavelength. The resonant wavelength suffers shift on application of pressure and hence, pressure can be sensed. We use Plane Wave Expansion (PWE) technique to analyze the band structure and 2D Finite Difference Time Domain (FDTD) technique to simulate light propagation in the considered design. Simulation results show that proposed sensor can operate in the pressure range of 0 GPa- 11 GPa with sensitivity of 7.53 nm/GPa.