Mobility in semiconducting carbon nanotubes at finite carrier density

Abstract

Carbon nanotube field-effect transistors operate over a wide range of electron or hole density, controlled by the gate voltage. Here we calculate the mobility in semiconducting nanotubes as a function of carrier density and electric field, for different tube diameters and temperature. The low-field mobility is a non-monotonic function of carrier density, and varies by as much as a factor of 4 at room temperature. At low density, with increasing field the drift velocity reaches a maximum and then exhibits negative differential mobility, due to the non-parabolicity of the bandstructure. At a critical density ${\rho }_c\sim$ 0.35-0.5 electrons/nm, the drift velocity saturates at around one third of the Fermi velocity. Above ${\rho }_c$, the velocity increases with field strength with no apparent saturation.

5 pages, 4 figures

References in corpus (7)

• Electron-Phonon Scattering in Metallic Single-Walled Carbon Nanotubes
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• Jahn-Teller instability in C6H6+ and C6H6- revisited

Cited by in corpus (8)

• Non-equilibrium Green's function treatment of phonon scattering in carbon nanotube transistors
• Multi-Band Mobility in Semiconducting Carbon Nanotubes
• Strong mobility degradation in ideal graphene nanoribbons due to phonon scattering
• Deformation Potential Carrier-Phonon Scattering in Semiconducting Carbon Nanotube Transistors
• Atomistic investigation of low-field mobility in graphene nanoribbons
• Microwave Rectification by a Carbon Nanotube Schottky Diode
• Shot noise suppression in quasi one-dimensional Field Effect Transistors
• Exciton dissociation in two-dimensional transition metal dichalcogenides: Excited states and substrate effects