Design of pressure sensor based on two-dimensional photonic crystal

Abstract

In this work, we design a new pressure sensor based on two-dimensional photonic crystal waveguide coupled to a point-defect resonant microcavity. The mechanism of sensing is based on the change of the germanium refractive index as function of the hydrostatic pressure P. The resonant wavelength will shift when pressure variation induces change in the refractive indexes of the structure. The pressure variation causes the shifting of defect modes. The properties of the refractive index sensor are simulated using the finite-difference time-domain algorithm and the plane wave expansion method. These kinds of sensors have many advantages in compactness, high sensitivity, and various choices of materials.