Negative Magnetoresistance in Graphene Quantum Dot Devices

ORAL

Abstract

Graphene quantum dot devices have unique transport properties that differ from graphene devices without a quantum dot structure. The opening of a quantum confinement gap and Joule heating of the graphene's electrons lead to an activation energy mediated conductance through the device. Our measurements on these devices in a magnetic field oriented perpendicular to the graphene show a negative magnetoresistance as high as 40% at 1.3 K that decreases with increasing temperature to 5% at 150 K. The activation energies in zero-field and under parallel field are equivalent, indicating that the formation of Landau levels in the graphene is responsible for the magnetoresistance. This opens the possibility to control the level filling with a gate electrode, leading to a tunable magnetoresistance.

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Presenters

  • DaVonne Henry

    • Georgetown University

Authors

  • DaVonne Henry

    • Georgetown University

  • Luke St. Marie

    • Georgetown University

  • Amjad Alqahtani

    • Georgetown University

  • Yijing Liu

    • Georgetown University

  • Rachael L Myers-Ward2

    • U.S. Naval Research Laboratory
    • United States Naval Research Laboratory
    • U.S. Naval Research Laboratory, Washington, DC
    • U.S. Naval Research Laboratory, Washington, DC 20375, USA

  • Kurt D Gaskill

    • U.S. Naval Research Laboratory
    • Institution for Research in Electronics and Applied Physics, University of Maryland, College Park MD
    • University of Maryland
    • Institution for Research in Electronics and Applied Physics, University of Maryland, College Park MD 20740

  • Albert F Rigosi

    • National Institute of Standards and Technology
    • National Institute of Standards and Tech

  • Abdel El Fatimy

    • Brno University of Technology
    • Mohammed VI Polytechnique University
    • Department of Physics, Université Mohammed VI Polytechnique, Ben Guerir 43150, Morocco
    • Central European Institute of Technology

  • Petr Neugebauer

    • Brno University of Technology, CEITEC
    • Ceitec Institute, Brno University
    • Central European Institute of Technology

  • Amy Y Liu

    • Georgetown University

  • Paola Barbara

    • Georgetown University