Theory of phonon-drag thermopower of extrinsic semiconducting single-wall carbon nanotubes and comparison with previous experimental data

Abstract

A theoretical model for the calculation of the phonon-drag thermopower, $S^g$, in degenerately doped semiconducting single-wall carbon nanotubes (SWCNTs) is proposed. Detailed calculations of $S^g$ are performed as a function of temperature, tube radius and position of the Fermi level. We derive a simple analytical expression for $S^g$ that can be utilized to determine the free carrier density in doped nanotubes. At low temperatures $S^g$ shows an activated behavior characteristic of the one-dimensional (1D) character of carriers. Screening effects are taken into account and it is found that they dramatically reduce the magnitude of $S^g$. Our results are compared with previous published experimental data in bulk p-doped SWCNT materials. Excellent agreement is obtained in the temperature range 10-200 K for a consistent set of parameters. This is a striking result in view of the complexity of these systems.

21 pages, 6 figures. This version has been accepted for publication in Phys. Rev. B

References in corpus (4)

• Deformation Potential Carrier-Phonon Scattering in Semiconducting Carbon Nanotube Transistors
• The Phonon Drag Effect in Single-Walled Carbon Nanotubes
• Phonon-phonon interactions and phonon damping in carbon nanotubes
• Restricted Wiedemann-Franz law and vanishing thermoelectric power in one-dimensional conductors

Cited by in corpus (1)

• Large phonon-drag enhancement induced by narrow quantum confinement at the LaAlO3/SrTiO3 interface