title: Extraordinary transmission of gigahertz surface acoustic waves.
abstract: Extraordinary transmission of waves, i.e. a transmission superior to the amount predicted by geometrical considerations of the aperture alone, has to date only been studied in the bulk. Here we present a new class of extraordinary transmission for waves confined in two dimensions to a flat surface. By means of acoustic numerical simulations in the gigahertz range, corresponding to acoustic wavelengths λ ~ 3-50 μm, we track the transmission of plane surface acoustic wave fronts between two silicon blocks joined by a deeply subwavelength bridge of variable length with or without an attached cavity. Several resonant modes of the structure, both one- and two-dimensional in nature, lead to extraordinary acoustic transmission, in this case with transmission efficiencies, i.e. intensity enhancements, up to ~23 and ~8 in the two respective cases. We show how the cavity shape and bridge size influence the extraordinary transmission efficiency. Applications include new metamaterials and subwavelength imaging.
authors.affiliation: Division of Applied Physics, Graduate School of Engineering, Hokkaido University, Sapporo 060-8628, Japan.
authors.forename: Sylvain
authors.initials: S
authors.lastname: Mezil
authors.affiliation: Division of Applied Physics, Graduate School of Engineering, Hokkaido University, Sapporo 060-8628, Japan.
authors.forename: Kazuki
authors.initials: K
authors.lastname: Chonan
authors.affiliation: Division of Applied Physics, Graduate School of Engineering, Hokkaido University, Sapporo 060-8628, Japan.
authors.forename: Paul H
authors.initials: PH
authors.lastname: Otsuka
authors.affiliation: Division of Applied Physics, Graduate School of Engineering, Hokkaido University, Sapporo 060-8628, Japan.
authors.forename: Motonobu
authors.initials: M
authors.lastname: Tomoda
authors.affiliation: Division of Applied Physics, Graduate School of Engineering, Hokkaido University, Sapporo 060-8628, Japan.
authors.forename: Osamu
authors.initials: O
authors.lastname: Matsuda
authors.affiliation: Institute of Physics and Applied Physics, Yonsei University, Seoul 120-749, Korea.
authors.forename: Sam H
authors.initials: SH
authors.lastname: Lee
authors.affiliation: Division of Applied Physics, Graduate School of Engineering, Hokkaido University, Sapporo 060-8628, Japan.
authors.forename: Oliver B
authors.initials: OB
authors.lastname: Wright