Condensed Matter Seminar

Nadya Mason
University of Illinois at Urbana-Champaign

Thursday, October 9, 2008
1:00 pm in SPL 52

Probing electron energies in carbon nanotubes

Abstract: In this talk I will discuss a new method of measuring electron energies and interactions in carbon nanotubes. Carbon nanotubes can be considered model one-dimensional systems whose transport is strongly affected by electron interactions. Using tunneling spectroscopy via a superconducting probe, we study the shape of the electron energy distribution functions, and hence energy relaxation rates, in nanotubes that have bias voltages applied between their ends. We find that at low temperatures electrons interact weakly in nanotubes of a few microns channel length, independent of end-to-end conductance values. Surprisingly, the energy relaxation rate can increase substantially when the temperature is raised to only 1.5 K. In general, tunneling spectroscopy with a superconducting probe may be a powerful new tool for characterizing electron behavior in carbon nanotubes.