Apparent strange metal behavior in small angle twisted bilayer graphene

 Shaffique Adam

Shaffique Adam, NUS

Strange metals are an intriguing class of materials that exhibit unconventional electronic properties, often characterized by a linear-in-temperature dependence of resistivity and a linear-in-field dependence of magnetotransport. In this work, we explore the behavior of twisted bilayer graphene as a specific example, where the moire potential can significantly modify the electronic structure. Our previous work has demonstrated that at small twist angles, the resistivity displays a linear-in-temperature behavior well below the Bloch–Gruneisen temperature.

Building on this result, we show that magnetotransport also exhibits a similar linear behavior over a wide range of magnetic fields. We determine the window in parameter space for the apparent strange metal behavior defined by the co-existence of linear-in-temperature resistivity and linear-in-field magnetotransport. Interestingly, our imitation strange metal becomes less robust for dirtier samples, which is in contrast to the behavior of real strange metals according to recent theories. These findings underscore the potential for ordinary metals to imitate strange metal behavior and the importance of careful interpretation of experimental results.

About the presenter

AI Shaffique Adam is currently an Associate Professor, Yale-NUS College and an NRF Fellow. A/Prof Adam is an expert in the theoretical physics of Dirac systems. Within FLEET, he is working on gaining an understanding of the electronic transport and other properties of novel Dirac semimetals, as well as the conventional insulator to topological insulator transition in such systems.