Length-dependent optical effects in single walled carbon nanotubes

Aruna Rajan, Michael S. Strano, Daniel A. Heller, Tobias Hertel, Klaus Schulten

Research output: Contribution to journalArticlepeer-review

Abstract

Recently, Heller et al. reported length-dependent effects on the relative photoluminescence (PL) quantum yield of single walled carbon nanotubes (SWNTs) [Heller et al J. Am. Chem. Soc. 2004, 126, 14567-14573]. We propose a simple model involving thermal diffusion of excitons along the nanotube axis and quenching at the ends, to explain the observed trend in their data. By fitting to our model, we extract a diffusion coefficient of 6 cm2/s for excitons in SWNTs. Assuming a mono exponential decay of exciton PL, we also predict that effective length-dependent PL lifetimes for these excitons lie in the range of 1 -27 ps. Experimental observations are shown to be consistent with stochastic rather than wavepacket-like exciton migration, which is in agreement with ultrafast excitonic dephasing. Edge effects seem to limit the use of short SWNTs in imaging and optical sensing applications.

Original languageEnglish (US)
Pages (from-to)6211-6213
Number of pages3
JournalJournal of Physical Chemistry B
Volume112
Issue number19
DOIs
StatePublished - May 15 2008
Externally publishedYes

ASJC Scopus subject areas

  • Physical and Theoretical Chemistry
  • Surfaces, Coatings and Films
  • Materials Chemistry

Fingerprint

Dive into the research topics of 'Length-dependent optical effects in single walled carbon nanotubes'. Together they form a unique fingerprint.

Cite this