Moiré Superlattices*

Moiré superlattices comprised of stacked two-dimensional materials present a versatile platform for engineering and investigating new emergent quantum states of matter. At present, the vast majority of investigated systems have long moiré wavelengths, but investigating these effects at shorter, incommensurate wavelengths remains a challenge. How can the electronic features of the superlattice be described when the continuum limit is no longer applicable? Do minibands still form in such short wavelength systems? We demonstrate that a relatively simple tight-binding model treating the effect of the moiré superlattice as an imposed, external potential can accurately describe the electronic structure of new short-wavelength minibands, and that our findings are supported by ab initio calculations. We present our results in tandem with angle-resolved photoemission spectroscopy (ARPES) measurements studying a short moiré wavelength of 0.5 nm for twisted graphene/WSe2, in which distinct minibands formed by the moiré potential are observed despite the sub-nanometer moiré wavelength.