Photonic-Plasmonic Hybrid 2D-Pillar Cavity for Mode Confinement With Subwavelength Volume

We present a two-dimensional photonic-plasmonic hybrid cavity design by exploring the photonic bandgap properties and the plasmonic characteristics. The FDTD simulation tool was used to optimize the cavity parameters. The design was achieved by introducing a layer of defect rods in the 2D-PhC pillar structure on a thin metal slab supported by a glass substrate. The excited defect mode is confined in the photonic-plasmonic bandgap, it is spatially restricted on the symmetry plane and the plasmonic characteristics offer enhanced confinement in the vertical plane close to the metal layer. The optimized size of the defect rods as well as the thickness of the metal layer can offer an enhanced Q factor of 850, and subwavelength mode volume of 0.07 (λ/n)
³
with a maximum intensity distribution is concentrated in the defect rods.