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Localization to delocalization probed by magnetotransport of hBN/graphene/hBN stacks in the ultra-clean regime.

ABSTRACT: We report on magnetotransport in a high-quality graphene device, which is based on monolayer graphene (Gr) encapsulated by hexagonal boron nitride (hBN) layers, i.e., hBN/Gr/hBN stacks. In the vicinity of the Dirac point, a negative magnetoconductance is observed for high temperatures > ~ 40 K, whereas it becomes positive for low temperatures ≤ ~ 40 K, which implies an interplay of quantum interferences in Dirac materials. The elastic scattering mechanism in hBN/Gr/hBN stacks contrasts with that of conventional graphene on SiO₂, and our ultra-clean graphene device shows nonzero magnetoconductance for high temperatures of up to 300 K.

SUBMITTER: Iwasaki T

PROVIDER: S-EPMC8458370 | biostudies-literature | 2021 Sep

REPOSITORIES: biostudies-literature

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Localization to delocalization probed by magnetotransport of hBN/graphene/hBN stacks in the ultra-clean regime.

Iwasaki Takuya T Moriyama Satoshi S Ahmad Nurul Fariha NF Komatsu Katsuyoshi K Watanabe Kenji K Taniguchi Takashi T Wakayama Yutaka Y Hashim Abdul Manaf AM Morita Yoshifumi Y Nakaharai Shu S

Scientific reports 20210922 1

We report on magnetotransport in a high-quality graphene device, which is based on monolayer graphene (Gr) encapsulated by hexagonal boron nitride (hBN) layers, i.e., hBN/Gr/hBN stacks. In the vicinity of the Dirac point, a negative magnetoconductance is observed for high temperatures > ~ 40 K, whereas it becomes positive for low temperatures ≤ ~ 40 K, which implies an interplay of quantum interferences in Dirac materials. The elastic scattering mechanism in hBN/Gr/hBN stacks contrasts with th ...[more]

PMID: 34552168

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