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Probing the mesoscopic size limit of quantum anomalous Hall insulators.

ABSTRACT: The inelastic scattering length (L_s) is a length scale of fundamental importance in condensed matters due to the relationship between inelastic scattering and quantum dephasing. In quantum anomalous Hall (QAH) materials, the mesoscopic length scale L_s plays an instrumental role in determining transport properties. Here we examine L_s in three regimes of the QAH system with distinct transport behaviors: the QAH, quantum critical, and insulating regimes. Although the resistance changes by five orders of magnitude when tuning between these distinct electronic phases, scaling analyses indicate a universal L_s among all regimes. Finally, mesoscopic scaled devices with sizes on the order of L_s were fabricated, enabling the direct detection of the value of L_s in QAH samples. Our results unveil the fundamental length scale that governs the transport behavior of QAH materials.

SUBMITTER: Deng P

PROVIDER: S-EPMC9307791 | biostudies-literature | 2022 Jul

REPOSITORIES: biostudies-literature

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Probing the mesoscopic size limit of quantum anomalous Hall insulators.

Deng Peng P Eckberg Christopher C Zhang Peng P Qiu Gang G Emmanouilidou Eve E Yin Gen G Chong Su Kong SK Tai Lixuan L Ni Ni N Wang Kang L KL

Nature communications 20220722 1

The inelastic scattering length (Ls) is a length scale of fundamental importance in condensed matters due to the relationship between inelastic scattering and quantum dephasing. In quantum anomalous Hall (QAH) materials, the mesoscopic length scale Ls plays an instrumental role in determining transport properties. Here we examine Ls in three regimes of the QAH system with distinct transport behaviors: the QAH, quantum critical, and insulating regimes. Although th ...[more]

PMID: 35869045

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