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Origin of band gaps in graphene on hexagonal boron nitride.

ABSTRACT: Recent progress in preparing well-controlled two-dimensional van der Waals heterojunctions has opened up a new frontier in materials physics. Here we address the intriguing energy gaps that are sometimes observed when a graphene sheet is placed on a hexagonal boron nitride substrate, demonstrating that they are produced by an interesting interplay between structural and electronic properties, including electronic many-body exchange interactions. Our theory is able to explain the observed gap behaviour by accounting first for the structural relaxation of graphene's carbon atoms when placed on a boron nitride substrate, and then for the influence of the substrate on low-energy ?-electrons located at relaxed carbon atom sites. The methods we employ can be applied to many other van der Waals heterojunctions.

SUBMITTER: Jung J

PROVIDER: S-EPMC4346636 | biostudies-literature | 2015

REPOSITORIES: biostudies-literature

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Origin of band gaps in graphene on hexagonal boron nitride.

Jung Jeil J DaSilva Ashley M AM MacDonald Allan H AH MacDonald Allan H AH Adam Shaffique S

Nature communications 20150219

Recent progress in preparing well-controlled two-dimensional van der Waals heterojunctions has opened up a new frontier in materials physics. Here we address the intriguing energy gaps that are sometimes observed when a graphene sheet is placed on a hexagonal boron nitride substrate, demonstrating that they are produced by an interesting interplay between structural and electronic properties, including electronic many-body exchange interactions. Our theory is able to explain the observed gap beh ...[more]

PMID: 25695638

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