Twisted Bilayer Graphene at the magic twist angle features flat energy bands, which lead to superconductivity and strong correlation physics. These unique properties are typically limited to a narrow range of twist angles around the magic angle with a small allowed tolerance. Here we report on a mechanism that enables flattening of the band-structure using coherent optical illumination, leading to emergence of flat isolated Floquet-Bloch bands. We show that the effect can be realized with relatively weak optical beams at the visible-infrared range (below the material bandwidth) and persist for a wide range of small twist angles, increasing the allowed twist tolerance by an order of magnitude. We discuss the conditions under which these bands exhibit a non-zero Chern number. These optically induced flat bands could potentially host strongly-correlated, non-equilibrium electronic states of matter.
@article{arxiv.1910.13510,
title = {Optically induced flat bands in twisted bilayer graphene},
author = {Or Katz and Gil Refael and Netanel H. Lindner},
journal= {arXiv preprint arXiv:1910.13510},
year = {2020}
}