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Title: Theory of Exciton Energy Transfer in Carbon Nanotube Composites

Here, we compute the exciton transfer (ET) rate between semiconducting single-wall carbon nanotubes (SWNTs). We show that the main reasons for the wide range of measured ET rates reported in the literature are (1) exciton confinement in local quantum wells stemming from disorder in the environment and (2) exciton thermalization between dark and bright states due to intratube scattering. The SWNT excitonic states are calculated by solving the Bethe–Salpeter equation using tight-binding basis functions. The ET rates due to intertube Coulomb interaction are computed via Fermi’s golden rule. In pristine samples, the ET rate between parallel (bundled) SWNTs of similar chirality is very high (~10 14 s –1), while the ET rate for dissimilar or nonparallel tubes is considerably lower (~10 12 s –1). Exciton confinement reduces the ET rate between same-chirality parallel SWNTs by 2 orders of magnitude but has little effect otherwise. Consequently, the ET rate in most measurements will be on the order of 10 12 s –1, regardless of the tube relative orientation or chirality. Exciton thermalization between bright and dark states further reduces the ET rate to ~10 11 s –1. The ET rate also increases with increasing temperature and decreases with increasing dielectric constantmore » of the surrounding medium.« less
Authors:
 [1] ;  [1] ;  [1] ;  [1]
  1. Univ. of Wisconsin-Madison, Madison, WI (United States)
Publication Date:
Grant/Contract Number:
SC0008712
Type:
Accepted Manuscript
Journal Name:
Journal of Physical Chemistry. C
Additional Journal Information:
Journal Volume: 120; Journal Issue: 30; Journal ID: ISSN 1932-7447
Publisher:
American Chemical Society
Research Org:
Univ. of Wisconsin-Madison, Madison, WI (United States)
Sponsoring Org:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
Country of Publication:
United States
Language:
English
Subject:
77 NANOSCIENCE AND NANOTECHNOLOGY
OSTI Identifier:
1434257

Davoody, A. H., Karimi, F., Arnold, M. S., and Knezevic, I.. Theory of Exciton Energy Transfer in Carbon Nanotube Composites. United States: N. p., Web. doi:10.1021/acs.jpcc.6b04050.
Davoody, A. H., Karimi, F., Arnold, M. S., & Knezevic, I.. Theory of Exciton Energy Transfer in Carbon Nanotube Composites. United States. doi:10.1021/acs.jpcc.6b04050.
Davoody, A. H., Karimi, F., Arnold, M. S., and Knezevic, I.. 2016. "Theory of Exciton Energy Transfer in Carbon Nanotube Composites". United States. doi:10.1021/acs.jpcc.6b04050. https://www.osti.gov/servlets/purl/1434257.
@article{osti_1434257,
title = {Theory of Exciton Energy Transfer in Carbon Nanotube Composites},
author = {Davoody, A. H. and Karimi, F. and Arnold, M. S. and Knezevic, I.},
abstractNote = {Here, we compute the exciton transfer (ET) rate between semiconducting single-wall carbon nanotubes (SWNTs). We show that the main reasons for the wide range of measured ET rates reported in the literature are (1) exciton confinement in local quantum wells stemming from disorder in the environment and (2) exciton thermalization between dark and bright states due to intratube scattering. The SWNT excitonic states are calculated by solving the Bethe–Salpeter equation using tight-binding basis functions. The ET rates due to intertube Coulomb interaction are computed via Fermi’s golden rule. In pristine samples, the ET rate between parallel (bundled) SWNTs of similar chirality is very high (~1014 s–1), while the ET rate for dissimilar or nonparallel tubes is considerably lower (~1012 s–1). Exciton confinement reduces the ET rate between same-chirality parallel SWNTs by 2 orders of magnitude but has little effect otherwise. Consequently, the ET rate in most measurements will be on the order of 1012 s–1, regardless of the tube relative orientation or chirality. Exciton thermalization between bright and dark states further reduces the ET rate to ~1011 s–1. The ET rate also increases with increasing temperature and decreases with increasing dielectric constant of the surrounding medium.},
doi = {10.1021/acs.jpcc.6b04050},
journal = {Journal of Physical Chemistry. C},
number = 30,
volume = 120,
place = {United States},
year = {2016},
month = {6}
}