Capacitance-based tunneling spectroscopy of monolayer graphene
ORAL
Abstract
Traditional tunneling measurements do not function on insulating samples as there is no means to extract a tunneling current from them. We instead utilize a pulsed tunneling technique that exploits capacitive detection in a vertical sample geometry. Using this approach, we can tunnel into fully insulating materials such as the quantum Hall states of graphene. Moreover, the energy resolution of the method is limited only by the sample temperature. We measure the tunneling conductance between a graphite tunneling electrode and monolayer graphene through an atomically thin layer of hexagonal boron nitride in high magnetic fields and over a large range of carrier densities in the quantum Hall regime. We observe unexpected energy splittings in the Landau levels for filling factors that place the Fermi level in the cyclotron gap.
*This work was supported by the Gordon and Betty Moore Foundation, through grant GBMF2931 as well as the STC Center for Integrated Quantum Materials, NSF Grant No. DMR-1231319.
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Presenters
Spencer Tomarken
Physics, Massachusetts Inst of Tech-MIT
Authors
Spencer Tomarken
Physics, Massachusetts Inst of Tech-MIT
Ahmet Demir
Massachusetts Inst of Tech-MIT
Physics, Massachusetts Inst of Tech-MIT
Kenji Watanabe
National Institute for Materials Science
NIMS
National Institute for Material Science
Advanced Materials Laboratory, National Institute for Materials Science
National Institute of Materials Science
Research Center for Functional Materials, National Institute for Materials Science
National Institute for Materials Science (NIMS
Advanced Materials Laboratory, NIMS
National Institute for Materials Science, Advanced Materials Laboratory
National Institue for Materials Science
National Institute of Material Science
National Institute for Matericals Science
Advanced Materials Laboratory
National Institute for Materials Science, 1-1 Namiki
Advanced materials laboratory, National institute for Materials Science
NIMS-Japan
Takashi Taniguchi
National Institute for Materials Science
NIMS
National Institute for Material Science
Advanced Materials Laboratory, National Institute for Materials Science
National Institute of Materials Science
Research Center for Functional Materials, National Institute for Materials Science
National Institute for Materials Science (NIMS
Advanced Materials Laboratory, NIMS
National Institute for Materials Science, Advanced Materials Laboratory
National Institue for Materials Science
National Institute of Material Science
National Institute for Matericals Science
Advanced Materials Laboratory
National Institute for Materials Science, 1-1 Namiki
