title: Modulation of nanocavity plasmonic emission by local molecular states of C60 on Au(111).
abstract: We investigate the modulation of C60 monolayers on the nanocavity plasmonic (NCP) emission on Au(111) by tunneling electron excitation from a scanning tunneling microscope (STM) tip. STM induced luminescence spectra show not only suppressed emission, but also significant redshift of NCP emission bands on the C60 molecules relative to the bare metal surface. The redshift, together with the bias- and coverage-dependent emission feature, indicates that the C60 molecules act beyond a pure dielectric spacer, their electronic states are heavily involved in the inelastic tunneling process for plasmonic emission. A modified quantum cutoff relation is proposed to explain qualitatively the observed emission feature at both bias polarities. We also demonstrate molecularly resolved optical contrast on the C60 monolayer and discuss the contrast mechanism briefly.
authors.affiliation: Hefei National Laboratory for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei, Anhui 230026, China.
authors.forename: Feng
authors.initials: F
authors.lastname: Geng
authors.forename: Yang
authors.initials: Y
authors.lastname: Zhang
authors.forename: Yunjie
authors.initials: Y
authors.lastname: Yu
authors.forename: Yanmin
authors.initials: Y
authors.lastname: Kuang
authors.forename: Yuan
authors.initials: Y
authors.lastname: Liao
authors.forename: Zhenchao
authors.initials: Z
authors.lastname: Dong
authors.forename: Jianguo
authors.initials: J
authors.lastname: Hou
mesh_terms: D037741:Fullerenes / Q000737:chemistry*; D006046:Gold / Q000737:chemistry*; D006801:Humans; D053768:Metal Nanoparticles / Q000737:chemistry*; D016252:Microscopy, Scanning Tunneling / Q000295:instrumentation*; D013499:Surface Properties
chemical_list: D037741:Fullerenes; D006046:Gold