Moir\'e superlattices of two-dimensional van der Waals materials have emerged as a powerful platform for designing electronic band structures and discovering emergent physical phenomena. A key concept involves the creation of long-wavelength periodic potential and moir\'e bands in a crystal through interlayer hybridization when two materials are overlaid. Here we demonstrate a new approach based on spatially periodic dielectric screening to create moir\'e bands in a monolayer semiconductor. It relies on reduced dielectric screening of the Coulomb interactions in monolayer semiconductors and their environmental dielectric-dependent electronic band structure. We observe optical transitions between moir\'e bands in monolayer WSe2 when it is placed close to small angle-misaligned graphene on hexagonal boron nitride. The moir\'e bands are a result of long-range Coulomb interactions, strongly gate-tunable, and can have versatile superlattice symmetries independent of the crystal lattice of the host material. Our result also demonstrates that monolayer semiconductors are sensitive local dielectric sensors.
@article{arxiv.2007.11706,
title = {Creation of moir\'e bands in a monolayer semiconductor by spatially periodic dielectric screening},
author = {Yang Xu and Connor Horn and Jiacheng Zhu and Yanhao Tang and Liguo Ma and Lizhong Li and Song Liu and Kenji Watanabe and Takashi Taniguchi and James C. Hone and Jie Shan and Kin Fai Mak},
journal= {arXiv preprint arXiv:2007.11706},
year = {2021}
}