Anti-Stokes photoluminescence in II-VI colloidal nanocrystals

• Tipo: Artigo em Revista Científica Internacional
• Data: 2002

Autores

Rakovich, YP (Autor) Outra; Filonovich, SA (Autor) Outra; Gomes, MJM (Autor) Outra; Donegan, JF (Autor) Outra; Talapin, DV (Autor) Outra; Rogach, AL (Autor) Outra; Eychmuller, A (Autor) Outra

Revista

Título: Physica Status Solidi (B): Basic Research

Vol. 229

Páginas: 449-452

ISSN: 0370-1972

Editora: Wiley-Blackwell

Indexação

ISI Web of Knowledge - 58 Citações

Scopus - 71 Citações

Outras Informações

ID Authenticus: P-000-RRK

DOI: 10.1002/1521-3951(200201)229:1<449::aid-pssb449>3.0.co;2-4

Abstract (EN): For the first time highly efficient photon energy up-conversion (anti-Stokes photoluminescence) has been observed in colloids of CdTe nanocrystals (NCs) and CdSe NCs covered by ZnS shell. The maximum magnitude of the up-converted blue shift DeltaE(UC)(max) = 335 meV was obtained for CdSe/ZnS NCs under excitation by a low-power He-Ne laser, The maximum efficiency for energy conversion was estimated to be about eta(max) = 2.7 x 10(-2) % at room temperature. The intensity of the anti-Stokes photoluminescence increases with temperature and shows a linear dependence on the excitation intensity. We suggest that subgap surface states are involved as intermediate states in the up-conversion process rather than nonlinear two-photon absorption or Auger processes.

Idioma: Inglês

Tipo (Avaliação Docente): Científica

Nº de páginas: 4