Flat bands in twisted bilayer transition metal dichalcogenides

Understand

The crystal structure of a material creates a periodic potential that electrons move through giving rise to the electronic band structure of the material.

• When two-dimensional materials are stacked, the twist angle between the layers becomes an additional degree freedom for the resulting heterostructure.
• As this angle changes, the electronic band structure is modified leading to the possibility of flat bands with localized states and enhanced electronic correlations.
• In transition metal dichalcogenides, flat bands have been theoretically predicted to occur for long moir\'e wavelengths over a range of twist angles around 0 and 60 degrees giving much wider versatility than magic angle twisted bilayer graphene.