Localized spins on graphene

The problem of a magnetic impurity, atomic or molecular, absorbed on top of a carbon atom in otherwise clean graphene is studied using the numerical renormalization group. The spectral, thermodynamic, and scattering properties of the impurity are described in detail. In the presence of a small magne...

Full description

Saved in:
Bibliographic Details
Published inPhysical review letters Vol. 102; no. 4; p. 046801
Main Authors Cornaglia, P S, Usaj, Gonzalo, Balseiro, C A
Format Journal Article
LanguageEnglish
Published United States 30.01.2009
Online AccessGet more information

Cover

More Information
Summary:The problem of a magnetic impurity, atomic or molecular, absorbed on top of a carbon atom in otherwise clean graphene is studied using the numerical renormalization group. The spectral, thermodynamic, and scattering properties of the impurity are described in detail. In the presence of a small magnetic field, the low-energy electronic features of graphene make it possible to inject spin-polarized currents through the impurity using a scanning tunneling microscope. Furthermore, the impurity scattering becomes strongly spin dependent and for a finite impurity concentration it leads to spin-polarized bulk currents and a large magnetoresistance. In gated graphene the impurity spin is Kondo screened at low temperatures. However, at temperatures larger than the Kondo temperature, the anomalous magnetotransport properties are recovered.
ISSN:0031-9007
DOI:10.1103/PhysRevLett.102.046801