Optical photonic crystal sensor based on U-shaped ring resonator

This work is a proposal for a new structure of voltage sensor based on photonic crystals; it is composed of U-shaped photonic crystal ring resonator placed between two waveguides. The sensors structures have been changed in order to improve important sensor parameters such as quality factor and transmission. A large quality factor induces a good light confinement in semiconductor defect, making the photon more sensitive to voltage variation. The studied device offers nearly 100% transmission efficiency and a quality factor about 24,064. The electro-optical materials properties are ideally suited for narrow-channel optical communication systems and sensing applications. The values of about 622.22 nm/RIU, 1.12 nm/V and 2.24 nm per kV/mm have been obtained for refractive index sensitivity (Sn), the voltage sensitivity (SV) and the electric field sensitivity (SE), respectively. The simulation results presented in this paper have been analyzed by the two-methods plane wave expansion (PWE) and finite-difference time-domain (FDTD) using the Rsoft software.