title: Metal-coated semiconductor nanostructures and simulation of photon extraction and coupling to optical fibers for a solid-state single-photon source.
abstract: We have realized metal-coated semiconductor nanostructures for a stable and efficient single-photon source (SPS) and demonstrated improved single-photon extraction efficiency by the selection of metals and nanostructures. We demonstrate with finite-difference time-domain (FDTD) simulations that inclination of a pillar sidewall, which changes the structure to a nanocone, is effective in improving the photon extraction efficiency. We demonstrate how such nanocone structures with inclined sidewalls are fabricated with reactive ion etching. With the optimized design, a photon extraction efficiency to outer airside as high as ~97% generated from a quantum dot in a nanocone structure is simulated, which is the important step in realizing SPS on-demand operations. We have also examined the direct contact of such a metal-embedded nanocone structure with a single-mode fiber facet as a simple and practical method for preparing fiber-coupled SPS and demonstrated practical coupling efficiencies of ~16% with FDTD simulation.
authors.affiliation: Research Institute for Electronic Science, Hokkaido University, Sapporo 001-0020, Japan.
authors.forename: Ikuo
authors.initials: I
authors.lastname: Suemune
authors.forename: Hideaki
authors.initials: H
authors.lastname: Nakajima
authors.forename: Xiangming
authors.initials: X
authors.lastname: Liu
authors.forename: Satoru
authors.initials: S
authors.lastname: Odashima
authors.forename: Tomoya
authors.initials: T
authors.lastname: Asano
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Iijima
authors.forename: Jae-Hoon
authors.initials: JH
authors.lastname: Huh
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Idutsu
authors.forename: Hirotaka
authors.initials: H
authors.lastname: Sasakura
authors.forename: Hidekazu
authors.initials: H
authors.lastname: Kumano