A Tunable Photonic Double Heterostructure Cavity on Ferroelectric Barium Titanate

We designed a photonic double heterostructure cavity on rectangular lattice with an incorporated slot waveguide, which shows high quality factor for both TE and TM modes despite an absence of complete bandgap. The confinement capability of the cavity has been studied using the finite difference time domain method. The ferroelectric barium titanate (BaTiO₃) is used as the base material of the proposed cavity. The dispersive and absorptive natures of the material have been incorporated in the calculations. The presence of the slot waveguide improved the quality factor of the cavity, confirming the existing results. Despite the absorptive nature of BaTiO₃, the finite extent of the photonic crystal and absence of complete bandgap, the calculated quality factor compares favorably with values reported previously in the literature.