Quantum critical scaling for finite-temperature Mott-like metal-insulator crossover in few-layered MoS2

Abstract

The dominant role of strong electron-electron interactions in driving two-dimensional metal-insulator transitions has long been debated, but its clear experimental demonstration is still not available. Here, we examine the finite-temperature transport behavior of few-layered MoS2 material in the vicinity of the density-driven metal-insulator transition, 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, and should open an exciting avenue for the study of strong correlation physics.