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arXiv · 2206.10771

Temperature dependent resistivity in the doped two dimensional metallic phase of mTMD bilayers

Seongjin Ahn·Sankar Das Sarma
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Abstract

Two recent experiments from Cornell and Columbia have reported insulator-to-metal transitions in two-dimensional (2D) moir\'e transition metal dichalcogenides (mTMD) induced by doping around half-filling, where the system is a Mott insulator. In the current work, we consider the temperature dependent resistivity of this metallic phase in the doped situation away from half-filling, arguing that it arises from the strongly temperature dependent 2D Friedel oscillations (i.e. finite momentum screening) associated with random quenched charged impurities, leading to the observed strongly increasing linear-in-$T$ resistivity in the metallic phase. Our theory appears to account for the temperature-dependent metallic resistivity for doping around half-filling of the effective moir\'e TMD band, showing that temperature-dependent screened Coulomb disorder is an essential ingredient of doped 2D mTMD physics.

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Seongjin Ahn, Sankar Das Sarma. 2022-06-21. Temperature dependent resistivity in the doped two dimensional metallic phase of mTMD bilayers. https://doi.org/10.1103/physrevb.106.l121404

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