Selective enhancement of surface-state emission and simultaneous quenching of interband transition in white-luminophor CdS nanocrystals using localized plasmon coupling

Ozel T., Soganci I. M., Nizamoglu S., Huyal I. O., Mutlugun E., Sapra S., ...More

NEW JOURNAL OF PHYSICS, vol.10, 2008 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 10
  • Publication Date: 2008
  • Doi Number: 10.1088/1367-2630/10/8/083035
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Abdullah Gül University Affiliated: No


We propose and demonstrate the controlled modification and selective enhancement of surface-state emission in white-luminophor CdS nanocrystals (NCs) by plasmon-coupling them with proximal metal nanostructures. By carefully designing nano-Ag films to match their localized plasmon resonance spectrally with the surface-state emission peak of CdS NCs, we experimentally show that the surface- state emission is substantially enhanced in the visible wavelength, while the interband (band-edge) transition at the shorter wavelength far away from the plasmon resonance is simultaneously significantly suppressed. With such plasmon tuning and consequent strong plasmon coupling specifically for the surface- state transitions, the surface- state emission is made stronger than the band- edge emission. This corresponds to an enhancement factor of 12.7-fold in the ratio of the surface- state peak emission to the band- edge peak emission of the plasmon-coupled film sample compared with that in solution. Such a plasmonic engineering of surface- state emission in trap-rich CdS white nanoluminophors holds great promise for future solid-state lighting.