title: Directional light beaming control by a subwavelength asymmetric surface structure.
abstract: We propose a direct experimental set-up to observe the directional beaming effect of surface plasmon. A single diffracted beam from an asymmetric-sided surface corrugation is demonstrated. A single subwavelength slit with an asymmetric structure was fabricated using a focused ion beam (FIB) onto a metal surface with a glass substrate. By means of surface plasmon (SP) diffraction, the directionality of the light can be changed by the period of the metallic gratings. We show corresponding numerical simulations achieved by a Rigorous Coupled-Wave Analysis (RCWA) method and a Finite-Difference Time-Domain (FDTD) method. The simulation results were in agreement with the experimental data.
authors.forename: Ding-Zheng
authors.initials: DZ
authors.lastname: Lin
authors.forename: Tsung-Dar
authors.initials: TD
authors.lastname: Cheng
authors.forename: Chin-Kai
authors.initials: CK
authors.lastname: Chang
authors.forename: Ji-Tian
authors.initials: JT
authors.lastname: Yeh
authors.forename: Jonq-Min
authors.initials: JM
authors.lastname: Liu
authors.forename: Chau-Shioung
authors.initials: CS
authors.lastname: Yeh
authors.forename: Chih-Kung
authors.initials: CK
authors.lastname: Lee