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Insulator-quantum Hall transitionin monolayer epitaxial graphene.

ABSTRACT: We report on magneto-transport measurements on low-density, large-area monolayer epitaxial graphene devices grown on SiC. We observe temperature (T)-independent crossing points in the longitudinal resistivity ?xx, which are signatures of the insulator-quantum Hall (I-QH) transition, in all three devices. Upon converting the raw data into longitudinal and Hall conductivities ?xx and ?xy, in the most disordered device, we observed T-driven flow diagram approximated by the semi-circle law as well as the T-independent point in ?xy near e2/h. We discuss our experimental results in the context of the evolution of the zero-energy Landau level at low magnetic fields B. We also compare the observed strongly insulating behaviour with metallic behaviour and the absence of the I-QH transition in graphene on SiO2 prepared by mechanical exfoliation.

SUBMITTER: Huang LI

PROVIDER: S-EPMC5134328 | biostudies-literature | 2016

REPOSITORIES: biostudies-literature

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Insulator-quantum Hall transitionin monolayer epitaxial graphene.

Huang Lung-I LI Yang Yanfei Y Elmquist Randolph E RE Lo Shun-Tsung ST Liu Fan-Hung FH Liang Chi-Te CT

RSC advances 20160722 76

We report on magneto-transport measurements on low-density, large-area monolayer epitaxial graphene devices grown on SiC. We observe temperature (T)-independent crossing points in the longitudinal resistivity ρxx, which are signatures of the insulator-quantum Hall (I-QH) transition, in all three devices. Upon converting the raw data into longitudinal and Hall conductivities σxx and σxy, in the most disordered device, we observed T-driven flow diagra ...[more]

PMID: 27920902

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