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arXiv · 1901.03710

Strange metal in magic-angle graphene with near Planckian dissipation

Yuan Cao·Debanjan Chowdhury·Daniel Rodan-Legrain·Oriol Rubies-Bigordà·Kenji Watanabe·Takashi Taniguchi·T. Senthil·Pablo Jarillo-Herrero
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Abstract

Recent experiments on magic-angle twisted bilayer graphene have discovered correlated insulating behavior and superconductivity at a fractional filling of an isolated narrow band. In this paper we show that magic-angle bilayer graphene exhibits another hallmark of strongly correlated systems --- a broad regime of $T-$linear resistivity above a small, density dependent, crossover temperature--- for a range of fillings near the correlated insulator. We also extract a transport "scattering rate", which satisfies a near Planckian form that is universally related to the ratio of $(k_BT/\hbar)$. Our results establish magic-angle bilayer graphene as a highly tunable platform to investigate strange metal behavior, which could shed light on this mysterious ubiquitous phase of correlated matter.

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Yuan Cao, Debanjan Chowdhury, Daniel Rodan-Legrain, Oriol Rubies-Bigordà, Kenji Watanabe, Takashi Taniguchi, T. Senthil, Pablo Jarillo-Herrero. 2019-01-11. Strange metal in magic-angle graphene with near Planckian dissipation. https://doi.org/10.1103/physrevlett.124.076801

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