Kiowski, Oliver and Arnold, Katharina and Lebedkin, Sergei and Hennrich, Frank and Kappes, Manfred M. (2007) Direct observation of deep excitonic states in the photoluminescence spectra of single-walled carbon nanotubes. PHYSICAL REVIEW LETTERS, 99 (23).
Full text is not hosted in this archive but may be available via the Official URL, or by requesting a copy from the corresponding author.
Official URL: http://link.aps.org/abstract/PRL/v99/e237402
Low-energy, dark excitonic states have recently been predicted to lie below the first bright (E-11) exciton in semiconducting single-walled carbon nanotubes [Phys. Rev. Lett. 93, 157402 (2004)]. Decay into such deep excitonic states is implicated as a mechanism which reduces photoluminescence quantum yields. In this study we report the first direct observation of deep excitons in SWNTs. Photoluminescence (PL) microscopy of suspended semiconducting single-walled carbon nanotubes (SWNTs) reveals weak emission satellites redshifted by similar to 38-45 and similar to 100-130 meV relative to the main E-11 PL emission peaks. Similar satellites, redshifted by 95-145 meV depending on nanotube species, were also found in PL measurements of ensembles of SWNTs in water-surfactant dispersions. The relative intensities of these deep exciton emission features depend on the nanotube surroundings.
|Subjects:||Physical Science > Nanophysics|
Physical Science > Photonics
|Deposited By:||Lesley Tobin|
|Deposited On:||26 Nov 2008 16:31|
|Last Modified:||09 Feb 2009 15:24|
Repository Staff Only: item control page