Abstract
Moiré materials have risen to the forefront of physics research because of their ability to realize a disparate set of fascinating physical phenomena in these systems. Besides interesting electronic properties, the moiré pattern has been suggested to be used as a magnifying glass for local strain and dislocations in van der Waals (vdW) systems. Here, we demonstrate the ability to create a custom-designed moiré magnifying glass to probe local atomic lattice rotations directly in tiny-angle twisted bilayer graphene (TBG). In tiny-angle TBG, a moiré periodic network of local subdegree lattice rotations, i.e., the structural reconstruction, occurs due to the vdW interlayer interaction. By introducing a small-period graphene moiré pattern as the magnifying glass, the local subdegree lattice rotations in the underlying tiny-angle TBG are magnified both in structure, i.e., the local moiré periods, and in electronic properties, i.e., energy separations between two low-energy van Hove singularities. Our results unveil the unique magnifying effects of the moiré pattern, and the reported method can be applied to probe the structural reconstruction in any vdW system.
- Received 14 July 2023
- Accepted 13 September 2023
DOI:https://doi.org/10.1103/PhysRevB.108.125429
©2023 American Physical Society