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Many-body interactions in quasi-freestanding graphene.

ABSTRACT: The Landau-Fermi liquid picture for quasiparticles assumes that charge carriers are dressed by many-body interactions, forming one of the fundamental theories of solids. Whether this picture still holds for a semimetal such as graphene at the neutrality point, i.e., when the chemical potential coincides with the Dirac point energy, is one of the long-standing puzzles in this field. Here we present such a study in quasi-freestanding graphene by using high-resolution angle-resolved photoemission spectroscopy. We see the electron-electron and electron-phonon interactions go through substantial changes when the semimetallic regime is approached, including renormalizations due to strong electron-electron interactions with similarities to marginal Fermi liquid behavior. These findings set a new benchmark in our understanding of many-body physics in graphene and a variety of novel materials with Dirac fermions.

SUBMITTER: Siegel DA

PROVIDER: S-EPMC3136305 | biostudies-literature | 2011 Jul

REPOSITORIES: biostudies-literature

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Many-body interactions in quasi-freestanding graphene.

Siegel David A DA Park Cheol-Hwan CH Hwang Choongyu C Deslippe Jack J Fedorov Alexei V AV Louie Steven G SG Lanzara Alessandra A

Proceedings of the National Academy of Sciences of the United States of America 20110627 28

The Landau-Fermi liquid picture for quasiparticles assumes that charge carriers are dressed by many-body interactions, forming one of the fundamental theories of solids. Whether this picture still holds for a semimetal such as graphene at the neutrality point, i.e., when the chemical potential coincides with the Dirac point energy, is one of the long-standing puzzles in this field. Here we present such a study in quasi-freestanding graphene by using high-resolution angle-resolved photoemission s ...[more]

PMID: 21709258

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