Origin Of Magnetism in Graphene Nanostructures

POSTER

Abstract

The magnetic orderings of traditional magnetic materials originate from their partially filled $d$- or $f$-electron bands. Surprisingly, theoretical and experimental studies show that graphene nanostructures which contain only $s$ and $p$ electrons can also exhibit magnetic ground states. On the basis of the bonding properties of $pi$-electrons, we propose a theoretical model to explain the origin of magnetism in graphene nanostructures. Our theory is justified via examples ranging from nanoflakes to nanoribbons. Our theory also provides a simple physical insight into Lieb's theorem about the ground state magnetic momentum of a bipartite system.

*Supported by DOE, award No. DEFG02-97ER45632 and DE-SC0002623

Authors

  • Wen Ying Ruan

    • School of Physics, Georgia Institute of Technology, Atlanta 30332, USA

  • Yiyang Sun

    • Department of Physics, Applied Physics, and Astronomy, Rensselaer Polytechnic Institute, Troy, NY 12180, USA

  • Shengbai Zhang

    • Rensselaer Polytechnic Institute
    • Department of Physics, Applied Physics, and Astronomy, Rensselaer Polytechnic Institute, Troy, NY 12180, USA

  • Mei-Yin Chou

    • Insitute of Atomic and Molecular Science, Academia Sinica, Taipei, Taiwan and Georgia Institute of Technology, Atlanta, Georgia, USA
    • School of Physics, Georgia Institute of Technology, Atlanta 30332, USA, and IAMS, Academia Sinica, Taipei, Taiwan
    • School of Physics, Georgia Institute of Technology, Atlanta, Georgia 30332, USA and Institute of Atomic and Molecular Sciences, Academia Sinica, Taipe