TY  - JOUR
A1  - Soavi, Giancarlo
A1  - Scotognella, Francesco
A1  - Viola, Daniele
A1  - Hefner, Timo
A1  - Hertel, Tobias
A1  - Cerullo, Giulio
A1  - Lanzani, Guglielmo
T1  - High energetic excitons in carbon nanotubes directly probe charge-carriers
JF  - Scientific Reports
N2  - Theory predicts peculiar features for excited-state dynamics in one dimension (1D) that are difficult to be observed experimentally. Single-walled carbon nanotubes (SWNTs) are an excellent approximation to 1D quantum confinement, due to their very high aspect ratio and low density of defects. Here we use ultrafast optical spectroscopy to probe photogenerated charge-carriers in (6,5) semiconducting SWNTs. We identify the transient energy shift of the highly polarizable S\(_{33}\) transition as a sensitive fingerprint of charge-carriers in SWNTs. By measuring the coherent phonon amplitude profile we obtain a precise estimate of the Stark-shift and discuss the binding energy of the S\(_{33}\) excitonic transition. From this, we infer that charge-carriers are formed instantaneously (<50 fs) even upon pumping the first exciton, S\(_{11}\). The decay of the photogenerated charge-carrier population is well described by a model for geminate recombination in 1D.
KW  - high energy
KW  - optical spectroscopy
KW  - carbon nanotubes and fullerenes
Y1  - 2015
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-143061
VL  - 5
IS  - 9681
ER  -