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Temperature dependence of electron density and electron-electron interactions in monolayer epitaxial graphene grown on SiC.

ABSTRACT: We report carrier density measurements and electron-electron (e-e) interactions in monolayer epitaxial graphene grown on SiC. The temperature (T)-independent carrier density determined from the Shubnikov-de Haas (SdH) oscillations clearly demonstrates that the observed logarithmic temperature dependence of Hall slope in our system must be due to e-e interactions. Since the electron density determined from conventional SdH measurements does not depend on e-e interactions based on Kohn's theorem, SdH experiments appear to be more reliable compared with the classical Hall effect when one studies the T dependence of the carrier density in the low T regime. On the other hand, the logarithmic T dependence of the Hall slope ?Rxy/?B can be used to probe e-e interactions even when the conventional conductivity method is not applicable due to strong electron-phonon scattering.

SUBMITTER: Liu CW

PROVIDER: S-EPMC5535274 | biostudies-literature | 2017 Jun

REPOSITORIES: biostudies-literature

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Temperature dependence of electron density and electron-electron interactions in monolayer epitaxial graphene grown on SiC.

Liu Chieh-Wen CW Chuang Chiashain C Yang Yanfei Y Elmquist Randolph E RE Ho Yi-Ju YJ Lee Hsin-Yen HY Liang Chi-Te CT

2d materials 20170125 2

We report carrier density measurements and electron-electron (e-e) interactions in monolayer epitaxial graphene grown on SiC. The temperature (T)-independent carrier density determined from the Shubnikov-de Haas (SdH) oscillations clearly demonstrates that the observed logarithmic temperature dependence of Hall slope in our system must be due to e-e interactions. Since the electron density determined from conventional SdH measurements does not depend on ...[more]

PMID: 28775850

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