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Observation of Landau levels on nitrogen-doped flat graphite surfaces without external magnetic fields.

ABSTRACT: Under perpendicular external magnetic fields, two-dimensional carriers exhibit Landau levels (LLs). However, it has recently been reported that LLs have been observed on graphene and graphite surfaces without external magnetic fields being applied. These anomalous LLs have been ascribed primarily to a strain of graphene sheets, leading to in-plane hopping modulation of electrons. Here, we report the observation of the LLs of massive Dirac fermions on atomically flat areas of a nitrogen-doped graphite surface in the absence of external magnetic fields. The corresponding magnetic fields were estimated to be as much as approximately 100 T. The generation of the LLs at the area with negligible strain can be explained by inequivalent hopping of π electrons that takes place at the perimeter of high-potential domains surrounded by positively charged substituted graphitic-nitrogen atoms.

SUBMITTER: Kondo T

PROVIDER: S-EPMC4637907 | biostudies-literature | 2015 Nov

REPOSITORIES: biostudies-literature

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Observation of Landau levels on nitrogen-doped flat graphite surfaces without external magnetic fields.

Kondo Takahiro T Guo Donghui D Shikano Taishi T Suzuki Tetsuya T Sakurai Masataka M Okada Susumu S Nakamura Junji J

Scientific reports 20151109

Under perpendicular external magnetic fields, two-dimensional carriers exhibit Landau levels (LLs). However, it has recently been reported that LLs have been observed on graphene and graphite surfaces without external magnetic fields being applied. These anomalous LLs have been ascribed primarily to a strain of graphene sheets, leading to in-plane hopping modulation of electrons. Here, we report the observation of the LLs of massive Dirac fermions on atomically flat areas of a nitrogen-doped gra ...[more]

PMID: 26549618

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