title: Surface-enhanced Raman scattering of rhodamine 6G on nanowire arrays decorated with gold nanoparticles.
abstract: We investigate the surface-enhanced Raman scattering (SERS) of rhodamine 6G (R6G) adsorbed on Au nanoparticles attached to InP nanowires. We find that nanowire arrays act as frameworks for effective SERS substrates with a significantly higher Raman signal sensitivity than a planar framework of Au nanoparticles adsorbed two-dimensionally on a flat surface. The SERS signal displays a clear polarization-dependent effect when the nanowires are arranged in a row. We also find that the SERS signal increases with time during continuous laser illumination. The plasmon-enhanced optical forces between Au nanoparticles may either move pairs of nanoparticles closer together or attract adsorbed molecules by moving them to the junctions of Au nanoparticle aggregates. Such effects by plasmon optical forces may cause the observed increase of the SERS signal with continuous laser illumination.
authors.affiliation: School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024, People's Republic of China. Beijing National Laboratory of Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, People's Republic of China.
authors.forename: Jianing
authors.initials: J
authors.lastname: Chen
authors.forename: Thomas
authors.initials: T
authors.lastname: Mårtensson
authors.forename: Kimberly A
authors.initials: KA
authors.lastname: Dick
authors.forename: Knut
authors.initials: K
authors.lastname: Deppert
authors.forename: H Q
authors.initials: HQ
authors.lastname: Xu
authors.forename: Lars
authors.initials: L
authors.lastname: Samuelson
authors.forename: Hongxing
authors.initials: H
authors.lastname: Xu