title: Terahertz Spectroscopy of Individual Single-Walled Carbon Nanotubes as a Probe of Luttinger Liquid Physics.
abstract: Luttinger liquid theory predicts that collective electron excitations due to strong electron-electron interactions in a one-dimensional (1D) system will result in a modification of the collective charge-propagation velocity. By utilizing a circuit model for an individual metallic single-walled carbon nanotube as a nanotransmission line, it has been shown that the frequency-dependent terahertz impedance of a carbon nanotube can probe this expected 1D Luttinger liquid behavior. We excite terahertz standing-wave resonances on individual antenna-coupled metallic single-walled carbon nanotubes. The terahertz signal is rectified using the nanotube contact nonlinearity, allowing for a low-frequency readout of the coupled terahertz current. The charge velocity on the nanotube is determined from the terahertz spectral response. Our measurements show that a carbon nanotube can behave as a Luttinger liquid system with charge-propagation velocities that are faster than the Fermi velocity. Understanding what determines the charge velocity in low-dimensional conductors is important for the development of next generation nanodevices.
authors.affiliation: Department of Applied Physics, Yale University , New Haven, Connecticut 06511, United States.
authors.forename: Joel D
authors.initials: JD
authors.lastname: Chudow
authors.affiliation: Department of Applied Physics, Yale University , New Haven, Connecticut 06511, United States.|Department of Physics, University of North Florida , Jacksonville, Florida 32224, United States.
authors.forename: Daniel F
authors.initials: DF
authors.lastname: Santavicca
authors.affiliation: Department of Applied Physics, Yale University , New Haven, Connecticut 06511, United States.
authors.forename: Daniel E
authors.initials: DE
authors.lastname: Prober
keywords: Carbon nanotubes; Luttinger liquid; one-dimensional conductors; terahertz spectroscopy