Strange metallicity of moir\'e twisted bilayer graphene

Abstract

Recent measurements in several different laboratories report the observation of an approximately linear-in-temperature resistivity with a large twist-angle-dependent slope (or temperature coefficient) in moir\'e twisted bilayer graphene (tBLG) down to a few K and sometimes to much lower temperatures. In this note, we theoretically discuss this `strange metal' linear-in-temperature transport behavior from the perspective of resistive scattering by acoustic phonons, emphasizing the aspects of the transport data, which are and which are not consistent with the phonon scattering mechanism. Extensive theoretical comparison with a new experiment [A. Jaoui et al., Nature Physics 18, 633 (2022)] is the central new aspect of this work.