Engineering Low-Disorder Superlattice Potentials in Graphene-Based Van der Waals Heterostructures

Long wavelength periodic potentials have led to the observation of a variety of electronic phenomena in graphene, including the Hofstadter butterfly, fractional Chern insulators, and flat band physics at zero magnetic field. Typically, such potentials arise due to Moiré patterns generated through lattice or rotationally mismatched layers. While Moiré patterns produce high quality, low-pitch potentials, they do not allow tuning of lattice strength, symmetry, or pitch. Here we present the fabrication of sub 40nm pitch, ultra-clean, lithographically defined metal superlattices. Using bulk capacitance measurements, we show that integrating the superlattices into a multilayer heterostructures allows controllable screening of the disorder potential while preserving a finite strength superlattice potential. I will present our progress towards engineering correlated states in artificial superlattices.