Long-range moiré tuning effect via inter-layer drag interaction.

Abstract

Constructing moiré superlattices has been demonstrated to be a powerful approach for tailoring the electronic properties of two-dimensional van der Waals materials. However, the periodic moiré potential diminishes rapidly away from the interface between the two stacked layers, restricting the moiré modulation only at the superlattice interface. Here, we present an alternative strategy to extend the influence range of the moiré tuning through drag interaction, a dynamic process involving inter-layer momentum/energy transfer mediated by Coulomb scatterings. By fabricating a unique electronic double-layer structure comprising a graphene moiré superlattice and a pristine graphene layer, we observe several intriguing inter-layer drag behaviors dominated by moiré physics. Notably, measuring the drag voltage within the pristine graphene layer, located distant from the moiré superlattice, reveals clear moiré tuning effects on the drag signal, including self-similar mapping spectra and the Hofstadter's butterfly spectra of drag resistance in the presence of a magnetic field. The realization of such moiré drag effect thus establishes a new paradigm for remote moiré engineering, offering a gateway to explore rich moiré physics in the emerging two-dimensional systems.