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arXiv · 2108.11464

Temperature-induced phase transitions in the quantum Hall magnet of bilayer graphene

Miuko Tanaka·Kenji Watanabe·Takashi Taniguchi·Kentaro Nomura·Seigo Tarucha·Michihisa Yamamoto
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Abstract

The quantum Hall system can be used to study many-body physics owing to its multiple internal electronic degrees of freedom and tunability. While quantum phase transitions have been studied intensively, research on the temperature-induced phase transitions of this system is limited. We measured the pure bulk conductivity of a quantum Hall antiferromagnetic state in bilayer graphene over a wide range of temperatures and revealed the two-step phase transition associated with the breaking of the long-range order and short-range antiferromagnetic order. Our findings are fundamental to understanding electron correlation in quantum Hall systems.

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Miuko Tanaka, Kenji Watanabe, Takashi Taniguchi, Kentaro Nomura, Seigo Tarucha, Michihisa Yamamoto. 2021-08-25. Temperature-induced phase transitions in the quantum Hall magnet of bilayer graphene. https://doi.org/10.1103/physrevb.105.075427

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