Phonon-induced giant linear-in- T resistivity in magic angle twisted bilayer graphene: Ordinary strangeness and exotic superconductivity

By Fengcheng Wu, E. Hwang. Physical review B, 2018

163 citations recorded by the source corpus.

We theoretically show that twisted bilayer graphene should have an enhanced linear-in-temperature resistivity in the metallic regime with the resistivity magnitude increasing as the twist angle approaches the magic angle ($\sim 1^{\circ}$). The slope of the resistivity versus temperature could approach a hundred of ohms per kelvin with a strong angle dependence, but with a rather weak dependence on the carrier density. This angle-tuned resistivity enhancement arises from the huge increase in the effective electron-phonon coupling in the system due to the suppression of graphene Fermi velocity induced by the flatband condition. Our calculated temperature dependence is reminiscent of the so-called `strange metal' transport behavior except that it is arising from the ordinary electron-phonon coupling in a rather unusual parameter space due to the generic moire flatband structure of twisted bilayer graphene.

Subfields: Atomic and Molecular Physics, and Optics, Materials Chemistry

View Paper: https://www.semanticscholar.org/paper/4ff9671b156b9271d8699a7d782cd154657b6f9c