Quantum critical scaling for finite temperature Mott-like metal-insulator crossover in a few layered-MoS$_2$

TL;DR

This study demonstrates that a few-layered MoS$_2$ undergoes a Mott-like metal-insulator transition driven by strong electron-electron interactions, revealing universal critical scaling behavior characteristic of correlated electron systems.

Contribution

It provides the first conclusive evidence of a disorder-independent, interaction-driven Mott transition in a two-dimensional transition-metal dichalcogenide, using finite-temperature transport and scaling analysis.

Findings

Transition driven by electron-electron interactions, not disorder

Universal critical scaling behavior observed near the transition

MoS$_2$ as a platform for studying strong correlation physics

Abstract

The possibility of the strong electron-electron interaction driven insulating phase from the metallic phase in two-dimensions has been suggested for clean systems without intentional disorder, but its rigorous demonstration is still lacking. Here, we examine the finite-temperature transport behavior of a few layered-MoS$_2$ material in the vicinity of the density-driven metal-insulator transition (MIT), revealing previously overlooked universal features characteristic of strongly correlated electron systems. Our scaling analysis, based on the Wigner-Mott theoretical viewpoint, conclusively demonstrates that the transition is driven by strong electron-electron interactions and not disorder, in striking resemblance to what is seen in other Mott systems. Our results provide compelling evidence that transition-metal dichalcogenides provide an ideal testing ground for the study of strong correlation physics, which should open an exciting avenue for future research, making a parallel with recent advances in twisted bilayer graphene