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Anisotropic Polarizability of Specific Semiconducting Nanotubes From Electro-Optical Measurements in Alternating Electric Fields
Published
Author(s)
Jeffrey A. Fagan, Vardhan Bajpai, Barry J. Bauer, Erik K. Hobbie
Abstract
Linear dichroism measurements on aqueous solutions of dispersed, size fractionated, single wall carbon nanotubes (SWNTs) are presented. The degree of SWNT alignment in response to applied alternating (AC) electric fields was measured at 3 kHz, for both the E11 and E22 transitions of the same semiconducting SWNTs. Measurement of the dichroism at specific wavelengths allows for the direct observation of the response to electric fields of individual (n,m) index SWNTs. The anisotropic polarizability of the DNA wrapped semiconducting single wall nanotubes measured here (L/D ca. 400) are found to be (8 ? 2) * 10-29 Fm2 at 3 kHz. An additional opto-electronic effect we believe to be related to the excitonic nature of the absorption peaks is also described.
Fagan, J.
, Bajpai, V.
, Bauer, B.
and Hobbie, E.
(2007),
Anisotropic Polarizability of Specific Semiconducting Nanotubes From Electro-Optical Measurements in Alternating Electric Fields, Journal of Physical Chemistry B, [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=852845
(Accessed October 23, 2025)