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arXiv · 2109.06812

Parallel transport and layer-resolved thermodynamic measurements in twisted bilayer graphene

Giulia Piccinini·Vaidotas Mišeikis·Kenji Watanabe·Takashi Taniguchi·Camilla Coletti·Sergio Pezzini
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Abstract

We employ dual-gated 30{\deg}-twisted bilayer graphene to demonstrate simultaneous ultra-high mobility and conductivity (up to 40 mS at room temperature), unattainable in a single-layer of graphene. We find quantitative agreement with a simple phenomenology of parallel conduction between two pristine graphene sheets, with a gate-controlled carrier distribution. Based on the parallel transport mechanism, we then introduce a method for in situ measurements of the chemical potential of the two layers. This twist-enabled approach, neither requiring a dielectric spacer, nor separate contacting, has the potential to greatly simplify the measurement of thermodynamic quantities in graphene-based systems of high current interest.

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Giulia Piccinini, Vaidotas Mišeikis, Kenji Watanabe, Takashi Taniguchi, Camilla Coletti, Sergio Pezzini. 2021-09-14. Parallel transport and layer-resolved thermodynamic measurements in twisted bilayer graphene. https://doi.org/10.1103/physrevb.104.l241410

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