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Updated: May 28, 2026

Atomically Traceable Nanostructure Fabrication
Published on: July 17, 2015
Intersubband edge singularity in metallic nanotubes
1Department of Physics and Astronomy, University of Utah, Salt Lake City, Utah 84112, USA.
Abstract:
The tunneling density of states of both the massless and massive (gapped) particles in metallic carbon nanotubes is known to have an anomalous energy dependence. This is the result of coupling to multiple low-energy bosonic excitation (plasmons). For both kinds of particles the ensuing effect is the suppression of the density of states by electron-electron interactions. We demonstrate that the optical absorption between gapless and gapped states is affected by the many-body effects in the opposite way. The absorption probability is enhanced compared with the noninteracting value and develops a power-law frequency dependence, A(ω) ∝ (ω - Δ)(-γ), where γ≈0.2 for typical nanotubes.
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