ZnO-Nanowire-Induced Nanocavities in Photonic Crystal Disks

We realize a novel type of nanowire-induced optical nanocavities based on photonic crystal disks, a design outperforming its one-dimensional and two-dimensional photonic crystal counterparts in terms of light–matter coupling. We implement this unique design using ZnO nanowires and SiN photonic crystal disks for a short-wavelength operation. We detail and assess the challenges of the fabrication process, a combination of SiN top-down processing techniques and nanowire nanomanipulation. We then investigate the optical properties of fabricated cavities and show that they present confined modes in the visible and the near-ultraviolet range with experimental quality factors up to Qexp = 2.4 × 103. We deduce from three-dimensional, finite-difference, time-domain calculations that such confined modes can present volumes as small as Vm = 1.3 (λ/nrdisk)3, for an exceptionally high confinement factor Γ = 47%. The high intensity enhancement ratios of confined modes confirm the high performance of these nanowire-indu...