Temperature dependence of electron density and electron–electron interactions in monolayer epitaxial graphene grown on SiC. (25th January 2017)

• Record Type: Journal Article
• Authors: Liu, Chieh-Wen; Chuang, Chiashain; Yang, Yanfei; Elmquist, Randolph E; Ho, Yi-Ju; Lee, Hsin-Yen; Liang, Chi-Te
• Is Part Of: 2D materials. Volume 4:Number 2(2017)
• Publication Date: 2017-01-25
• Subjects: graphene -- Shubnikov–de Haas -- electron–electron interactions -- carrier density; Graphene -- Periodicals; Materials science -- Periodicals; Nanostructured materials -- Periodicals; 620.115
• DOI: 10.1088/2053-1583/aa55b9
• Languages: English
• ISSNs: 2053-1583

Abstract

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 the 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 δR xy / δB can be used to probe e – e interactions even when the conventional conductivity method is not applicable due to strong electron–phonon scattering.