title: Ultra sub-wavelength surface plasmon confinement using air-gap, sub-wavelength ring resonator arrays.
abstract: Arrays of sub-wavelength, sub-10 nm air-gap plasmonic ring resonators are fabricated using nanoimprinting. In near infra-red (NIR) range, the resonator supports a single dipole mode which is excited and identified via simple normal illumination and explored through transmission measurements. By controlling both lateral and vertical confinement via a metal edge, the mode volume is successfully reduced down to 1.3 × 10(-5) λ0(3). The advantage of such mode confinement is demonstrated by applying the resonators biosensing. Using bovine serum albumin (BSA) molecules, a dramatic enhancement of surface sensitivity up to 69 nm/nm is achieved as the modal height approaches the thickness of the adsorbed molecule layers.
authors.affiliation: Korea Advanced Institute of Science and Technology, Department of Physics, 373-1 Guseong-dong, Yuseong-Gu, Daejeon, South Korea.
authors.forename: Jaehak
authors.initials: J
authors.lastname: Lee
authors.affiliation: Korea Institute of Machinery &Materials, 156 Gajeongbuk-Ro, Yuseong-Gu, Daejeon, South Korea.
authors.forename: Sangkeun
authors.initials: S
authors.lastname: Sung
authors.affiliation: Korea Institute of Machinery &Materials, 156 Gajeongbuk-Ro, Yuseong-Gu, Daejeon, South Korea.
authors.forename: Jun-Hyuk
authors.initials: JH
authors.lastname: Choi
authors.affiliation: Korea Advanced Institute of Science and Technology, Department of Physics, 373-1 Guseong-dong, Yuseong-Gu, Daejeon, South Korea.
authors.forename: Seok Chan
authors.initials: SC
authors.lastname: Eom
authors.affiliation: Technical University of Denmark, Department of Photonics Engineering, DK-2800 Kongens Lyngby, Denmark.
authors.forename: N Asger
authors.initials: NA
authors.lastname: Mortensen
authors.affiliation: Korea Advanced Institute of Science and Technology, Graduate School of Nanoscience and Technology, 373-1 Guseong-dong, Yuseong-Gu, Daejeon, South Korea.|Korea Advanced Institute of Science and Technology, Department of Physics, 373-1 Guseong-dong, Yuseong-Gu, Daejeon, South Korea.
authors.forename: Jung H
authors.initials: JH
authors.lastname: Shin