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11:42
Fabrication of Gate-tunable Graphene Devices for Scanning Tunneling Microscopy Studies with Coulomb Impurities
Published on: July 24, 2015
Many-body orbital paramagnetism in doped graphene sheets
A Principi1, Marco Polini, G Vignale
1NEST, Istituto Nanoscienze-CNR and Scuola Normale Superiore, I-56126 Pisa, Italy.
Physical Review Letters
|September 28, 2010
Summary
The orbital magnetic susceptibility of Dirac fermions is zero unless Coulomb interactions are considered. Many-body effects precisely control this susceptibility in doped graphene sheets.
Area of Science:
- Condensed matter physics
- Materials science
Background:
- The orbital magnetic susceptibility of noninteracting massless Dirac fermions is zero away from the Dirac point.
- Understanding many-body effects is crucial for characterizing unique electronic properties.
Purpose of the Study:
- To calculate the orbital magnetic susceptibility of massless Dirac fermions including Coulomb interaction.
- To investigate the role of many-body effects in doped graphene sheets.
Main Methods:
- Diagrammatic perturbation theory was employed for exact calculation.
- First-order perturbation in Coulomb interaction was considered.
Main Results:
- The orbital magnetic susceptibility is finite and positive when Coulomb interaction is included.
- Many-body effects significantly influence the susceptibility.
Conclusions:
- Doped graphene sheets exhibit orbital magnetic susceptibility controlled by many-body effects.
- These systems present unique phenomena driven by electron interactions.
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