Electron-phonon interaction in ultrasmall-radius carbon nanotubes

Abstract

We perform analysis of the band structure, phonon dispersion, and electron-phonon interactions in three types of small-radius carbon nanotubes. We find that the (5,5) can be described well by the zone-folding method and the electron-phonon interaction is too small to support either a charge-density wave or superconductivity at realistic temperatures. For ultra-small (5,0) and (6,0) nanotubes we find that the large curvature makes these tubes metallic with a large density of states at the Fermi energy and leads to unusual electron-phonon interactions, with the dominant coupling coming from the out-of-plane phonon modes. By combining the frozen-phonon approximation with the RPA analysis of the giant Kohn anomaly in 1d we find parameters of the effective Frölich Hamiltonian for the conduction electrons. Neglecting Coulomb interactions, we find that the (5,5) CNT remains stable to instabilities of the Fermi surface down to very low temperatures while for the (5,0) and (6,0) CNTs a CDW instability will occur. When we include a realistic model of Coulomb interaction we find that the charge-density wave remains dominant in the (6,0) CNT with $T_{\mathrm{CDW}}$ around 5 K while the charge-density wave instability is suppressed to very low temperatures in the (5,0) CNT, making superconductivity dominant with transition temperature around one Kelvin.

20 pages. Updated 7/23/04

References in corpus (10)

• Applications of a tight-binding total energy method for transition and noble metals: Elastic Constants, Vacancies, and Surfaces of Monatomic Metals
• Superconductivity in Ropes of Single-Walled Carbon Nanotubes
• A systematic ab-initio study of curvature effects in carbon nanotubes
• Correlated transport and non-Fermi liquid behavior in single-wall carbon nanotubes
• Acoustic phonon exchange, attractive interactions, and the Wentzel-Bardeen singularity in single-wall nanotubes
• Wentzel-Bardeen singularity and phase diagram for interacting electrons coupled to acoustic phonons in one dimension
• Microscopic model of superconductivity in carbon nanotubes
• On superconductivity in armchair carbon nanotubes
• Electron-phonon coupling and Peierls transition in metallic nanotubes
• Singlet superconductivity phase in carbon nanotubes

Cited by in corpus (19)

• Optical Phonons in Carbon Nanotubes: Kohn Anomalies, Peierls Distortions and Dynamic Effects
• Phonon Linewidths and Electron Phonon Coupling in Nanotubes
• High-Tc superconductivity in entirely end-bonded multi-walled carbon nanotubes
• Fundamental Optical Processes in Armchair Carbon Nanotubes
• Theory of superconductivity of carbon nanotubes and graphene
• Resonant Raman Spectroscopy of Armchair Carbon Nanotubes: Absence of "Metallic" Signature
• Coulomb screening and electronic instabilities of small-diameter (5,0) nanotubes
• Phonon-phonon interactions and phonon damping in carbon nanotubes
• AA stacking, tribological and electronic properties of double-layer graphene with krypton spacer
• Meissner effect in honeycomb arrays of multi-walled carbon nanotubes
• Electron spin relaxation in semiconducting carbon nanotubes: the role of hyperfine interaction
• Superconducting instability in 3 band metallic nanotubes
• Graphene-based nanodynamometer
• Electronic instabilities in 3D arrays of small-diameter (3,3) carbon nanotubes
• Length-dependent resistance model for a single-wall Carbon nanotube
• Current instability and diamagnetism in small-diameter carbon nanotubes
• Interwall conductance in double-walled armchair carbon nanotubes
• Influence of electron-phonon coupling on low temperature phases of metallic single-wall carbon nanotubes
• Importance of Non-Adiabatic Effects on Kohn Anomalies in 1D metals