Abstract-Terahertz Spectroscopy of Individual Single-Walled Carbon Nanotubes as a Probe of Luttinger Liquid Physics

Joel D. Chudow†, Daniel F. Santavicca†‡, and Daniel E. Prober*†

† Department of Applied Physics, Yale University, New Haven, Connecticut 06511, United States

‡ Department of Physics, University of North Florida, Jacksonville, Florida 32224, United States

Nano Lett., Article ASAP

DOI: 10.1021/acs.nanolett.6b01485

Publication Date (Web): July 20, 2016

Copyright © 2016 American Chemical Society

*E-mail: daniel.prober@yale.edu.

http://pubs.acs.org/doi/abs/10.1021/acs.nanolett.6b01485

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.