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arXiv · 1004.5473

Kohn Anomaly in Raman Spectroscopy of Single Wall Carbon Nanotubes

K. Sasaki·H. Farhat·R. Saito·M. S. Dresselhaus
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Abstract

Phonon softening phenomena of the $Γ$ point optical modes including the longitudinal optical mode, transverse optical mode and radial breathing mode in "metallic" single wall carbon nanotubes are reviewed from a theoretical point of view. The effect of the curvature-induced mini-energy gap on the phonon softening which depends on the Fermi energy and chirality of the nanotube is the main subject of this article. We adopt an effective-mass model with a deformation-induced gauge field which provides us with a unified way to discuss the curvature effect and the electron-phonon interaction.

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K. Sasaki, H. Farhat, R. Saito, M. S. Dresselhaus. 2010-04-30. Kohn Anomaly in Raman Spectroscopy of Single Wall Carbon Nanotubes. https://doi.org/10.1016/j.physe.2010.03.007

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