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arXiv · 0705.2260

pi-Electron theory of transverse optical excitons in semiconducting single-walled carbon nanotubes

Zhendong Wang·Hongbo Zhao·Sumit Mazumdar
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Abstract

We present a quantitative theory of optical absorption polarized transverse to the tube axes in semiconducting single-walled carbon nanotubes. Transverse optical absorption in semiconducting single-walled carbon nanotubes is to an exciton state that is strongly blueshifted, relative to the two lowest longitudinal excitons, by electron-electron interactions. The binding energy of the transverse exciton is considerably smaller than those of the longitudinal excitons. Electron-electron interactions also reduce the relative oscillator strength of the transverse optical absorption. Our theoretical results are in excellent agreement with recent experimental measurements in four chiral nanotubes.

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Zhendong Wang, Hongbo Zhao, Sumit Mazumdar. 2007-09-04. pi-Electron theory of transverse optical excitons in semiconducting single-walled carbon nanotubes. https://doi.org/10.1103/physrevb.76.115431

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