Length dependent transport measurements in long channel semiconducting carbon nanotubes

ORAL

Abstract

In order to understand the intrinsic electronic properties of CNTs, it is important to eliminate the contact effects from the measurements. We accomplish this by using a conductive-tip atomic force microscope cantilever as a movable electrode to obtain length dependent transport measurements. We report on the resistance versus length$ R(L)$ for several long channel ($L$ up to 130 $\mu $m) semiconducting CNTs at room temperature. In the on state,$ R(L)$ of semiconducting CNTs is linear. In the depleted state, $R(L)$ is linear for long channel lengths ($>$ 10 $\mu $m), but non-linear for short channel lengths due to the long depletion lengths in one-dimensional semiconductors. Transport remains diffusive under all depletion conditions, due to both low disorder and high temperature.

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Authors

  • Tarek Ghanem

    • Department of Physics and Center for Nanophysics and Advanced Materials, University of Maryland, College Park, MD 20742-4111, USA

  • Ellen Williams

    • University of Maryland, College Park
    • Department of Physics and University of Maryland Materials Research Science and Engineering Center, University of Maryland, College Park, MD 20742
    • University of Maryland
    • LPS, CNAM, and the DOP, UM
    • Physics Department, University of Maryland, College Park, MD 20742
    • Materials Research Science and Engineering Center, Center for Nanophysics and Advanced Materials, Dept of Physics, Univ. of Maryland, College Park, MD
    • University of Maryland College Park
    • Dept. of Physics, U. of Maryland - College Park
    • Department of Physics and Center for Nanophysics and Advanced Materials, University of Maryland, College Park, MD 20742-4111, USA

  • Michael Fuhrer

    • University of Maryland
    • Department of Physics and Center for Nanophysics and Advanced Materials, University of Maryland College Park
    • Department of Physics and Center for Nanophysics and Advanced Materials, University of Maryland, College Park, MD 20742, USA
    • Materials Research Science and Engineering Center, Center for Nanophysics and Advanced Materials, Dept of Physics, Univ. of Maryland, College Park, MD
    • Materials Research Science and Engineering Center and Center for Nanophysics and Advanced Materials, Department of Physics, University of Maryland
    • Department of Physics and Center for Nanophysics and Advanced Materials, University of Maryland, College Park, MD 20742-4111, USA