Letter | Published:

Half-metallic graphene nanoribbons

Naturevolume 444pages347349 (2006) | Download Citation


  • A Corrigendum to this article was published on 15 March 2007


Electrical current can be completely spin polarized in a class of materials known as half-metals, as a result of the coexistence of metallic nature for electrons with one spin orientation and insulating nature for electrons with the other. Such asymmetric electronic states for the different spins have been predicted for some ferromagnetic metals—for example, the Heusler compounds1—and were first observed in a manganese perovskite2. In view of the potential for use of this property in realizing spin-based electronics, substantial efforts have been made to search for half-metallic materials3,4. However, organic materials have hardly been investigated in this context even though carbon-based nanostructures hold significant promise for future electronic devices5. Here we predict half-metallicity in nanometre-scale graphene ribbons by using first-principles calculations. We show that this phenomenon is realizable if in-plane homogeneous electric fields are applied across the zigzag-shaped edges of the graphene nanoribbons, and that their magnetic properties can be controlled by the external electric fields. The results are not only of scientific interest in the interplay between electric fields and electronic spin degree of freedom in solids6,7 but may also open a new path to explore spintronics3 at the nanometre scale, based on graphene8,9,10,11.

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We thank J. Neaton, F. Giustino, I. Souza, C. H. Park and H. J. Choi for discussions. This research was supported by the National Science Foundation (NSF) and by the Director, Office of Science, Office of Basic Energy Science, Division of Material Sciences and Engineering, US Department of Energy (DOE). Computational resources have been provided by the NSF at the National Partnership for Advanced Computational Infrastructure and by the DOE at the National Energy Research Scientific Computing Center.

Author information


  1. Department of Physics, University of California at Berkeley, Berkeley, California, 94720, USA

    • Young-Woo Son
    • , Marvin L. Cohen
    •  & Steven G. Louie
  2. Materials Sciences Division, Lawrence Berkeley National Laboratory, California, 94720, Berkeley, USA

    • Young-Woo Son
    • , Marvin L. Cohen
    •  & Steven G. Louie


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Reprints and permissions information is available at www.nature.com/reprints. The authors declare no competing financial interests.

Corresponding author

Correspondence to Steven G. Louie.

Supplementary information

  1. Supplementary Figure 1

    Robustness half-metallicity in defective graphene nanoribbons. (PDF 155 kb)

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