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arXiv · 1603.00757

Giant Frictional Drag in Double Bilayer Graphene Heterostructures

Kayoung Lee·Jiamin Xue·David C. Dillen·Kenji Watanabe·Takashi Taniguchi·Emanuel Tutuc
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Abstract

We study the frictional drag between carriers in two bilayer graphene flakes separated by a 2 $-$ 5 nm thick hexagonal boron nitride dielectric. At temperatures ($T$) lower than $\sim$ 10 K, we observe a large anomalous negative drag emerging predominantly near the drag layer charge neutrality. The anomalous drag resistivity increases dramatically with reducing {\it T}, and becomes comparable to the layer resistivity at the lowest {\it T} = 1.5 K. At low $T$ the drag resistivity exhibits a breakdown of layer reciprocity. A comparison of the drag resistivity and the drag layer Peltier coefficient suggests a thermoelectric origin of this anomalous drag.

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Kayoung Lee, Jiamin Xue, David C. Dillen, Kenji Watanabe, Takashi Taniguchi, Emanuel Tutuc. 2016-03-02. Giant Frictional Drag in Double Bilayer Graphene Heterostructures. https://doi.org/10.1103/physrevlett.117.046803

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