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.

DOI: 10.1364/OE.20.026725

Cite this paper

@article{Geng2012ModulationON, title={Modulation of nanocavity plasmonic emission by local molecular states of C60 on Au(111).}, author={Feng Geng and Yang Zhang and Yunjie Yu and Yanmin Kuang and Yuan Liao and Zhenchao Dong and Jianguo Hou}, journal={Optics express}, year={2012}, volume={20 24}, pages={26725-35} }