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Transport gap in SmB₆ protected against disorder.

ABSTRACT: The inverted resistance method was used in this study to extend the bulk resistivity of [Formula: see text] to a regime where the surface conduction overwhelms the bulk. Remarkably, regardless of the large off-stoichiometric growth conditions (inducing disorder by samarium vacancies, boron interstitials, etc.), the bulk resistivity shows an intrinsic thermally activated behavior that changes ∼7-10 orders of magnitude, suggesting that [Formula: see text] is an ideal insulator that is immune to disorder.

SUBMITTER: Eo YS

PROVIDER: S-EPMC6601007 | biostudies-literature | 2019 Jun

REPOSITORIES: biostudies-literature

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Transport gap in SmB6 protected against disorder.

Eo Yun Suk YS Rakoski Alexa A Lucien Juniar J Mihaliov Dmitri D Kurdak Çağlıyan Ç Rosa Priscila F S PFS Fisk Zachary Z

Proceedings of the National Academy of Sciences of the United States of America 20190610 26

The inverted resistance method was used in this study to extend the bulk resistivity of [Formula: see text] to a regime where the surface conduction overwhelms the bulk. Remarkably, regardless of the large off-stoichiometric growth conditions (inducing disorder by samarium vacancies, boron interstitials, etc.), the bulk resistivity shows an intrinsic thermally activated behavior that changes ∼7-10 orders of magnitude, suggesting that [Formula: see text] is an ideal insulator that is immune to di ...[more]

PMID: 31182612

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