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arXiv · 2401.08050

Magneto-Thermoelectric Transport in Graphene Quantum Dot with Strong Correlations

Laurel E. Anderson·Antti Laitinen·Andrew Zimmerman·Thomas Werkmeister·Leyna Shackleton·Alexander Kruchkov·Takashi Taniguchi·Kenji Watanabe·Subir Sachdev·Philip Kim
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Abstract

Disorder at the etched edges of graphene quantum dots (GQD) enables random all-to-all interactions between localized charges in partially-filled Landau levels, providing a potential platform to realize the Sachdev-Ye-Kitaev (SYK) model. We use quantum Hall edge states in the graphene electrodes to measure electrical conductance and thermoelectric power across the GQD. We observe a rapid diminishing of electric conductance fluctuations and slowly decreasing thermoelectric power across the GQD with increasing temperature, consistent with recent theoretical predictions for the SYK regime.

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Laurel E. Anderson, Antti Laitinen, Andrew Zimmerman, Thomas Werkmeister, Leyna Shackleton, Alexander Kruchkov, Takashi Taniguchi, Kenji Watanabe, Subir Sachdev, Philip Kim. 2024-01-16. Magneto-Thermoelectric Transport in Graphene Quantum Dot with Strong Correlations. https://doi.org/10.1103/physrevlett.132.246502

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