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Capillary force-induced superlattice variation atop a nanometer-wide graphene flake and its moire origin studied by STM.

ABSTRACT: We present strong experimental evidence for the moiré origin of superlattices on graphite by imaging a live transition from one superlattice to another with concurrent and direct measurement of the orientation angle before and after rotation using scanning tunneling microscopy (STM). This has been possible due to a fortuitous observation of a superlattice on a nanometer-sized graphene flake wherein we have induced a further rotation of the flake utilizing the capillary forces at play at a solid-liquid interface using STM tip motion. We propose a more "realistic" tip-surface meniscus relevant to STM at solid-liquid interfaces and show that the capillary force is sufficient to account for the total expenditure of energy involved in the process.

SUBMITTER: Thomas LK

PROVIDER: S-EPMC6466726 | biostudies-literature | 2019

REPOSITORIES: biostudies-literature

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Capillary force-induced superlattice variation atop a nanometer-wide graphene flake and its moiré origin studied by STM.

Thomas Loji K LK Reichling Michael M

Beilstein journal of nanotechnology 20190401

We present strong experimental evidence for the moiré origin of superlattices on graphite by imaging a live transition from one superlattice to another with concurrent and direct measurement of the orientation angle before and after rotation using scanning tunneling microscopy (STM). This has been possible due to a fortuitous observation of a superlattice on a nanometer-sized graphene flake wherein we have induced a further rotation of the flake utilizing the capillary forces at play at a solid- ...[more]

PMID: 31019867

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