In this paper, we present an ultra-compact 1D photonic crystal(Ph C) Bragg grating design on a thin film lithium niobate slot waveguide(SWG) via 2D-and 3D-FDTD simulations. 2D-FDTD simulations are employed to tune the photonic bandgap(PBG) size, PBG center, cavity resonance wavelength, and the whole size of Ph C. 3DFDTD simulations are carried out to model the real structure by varying different geometrical parameters such as SWG height and Ph C size. A moderate resonance quality factor Q of about 300 is achieved with a Ph C size of only 0.5 μm× 0.7 μm× 6 μm. The proposed slot Bragg grating structure is then exploited as an electric field(E-field) sensor. The sensitivity is analyzed by 3D-FDTD simulations with a minimum detectable E-field as small as 23 m V∕m. The possible fabrication process of the proposed structure is also discussed. The compact size of the proposed slot Bragg grating structure may have applications in on-chip E-field sensing, optical filtering, etc.
In this paper, we present an ultra-compact 1D photonic crystal (PhC) Bragg grating design on a thin film lithium niobate slot waveguide (SWG) via 2D- and 3D-FDTD simulations. 2D-FDTD simulations are employed to tune the photonic bandgap (PBG) size, PBG center, cavity resonance wavelength, and the whole size of PhC. 3D-FDTD simulations are carried out to model the real structure by varying different geometrical parameters such as SWG height and PhC size. A moderate resonance quality factor Q of about 300 is achieved with a PhC size of only 0.5 mu m x 0.7 mu m x 6 mu m. The proposed slot Bragg grating structure is then exploited as an electric field (E-field) sensor. The sensitivity is analyzed by 3D-FDTD simulations with a minimum detectable E-field as small as 23 mV/m. The possible fabrication process of the proposed structure is also discussed. The compact size of the proposed slot Bragg grating structure may have applications in on-chip E-field sensing, optical filtering, etc. (C) 2017 Chinese Laser Press