Engineering Three-Dimensional Moiré Flat Bands.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 34516114.
- Also identified by DOI 10.1021/acs.nanolett.1c01684 and PMC identifier 8461648.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
Twisting two adjacent layers of van der Waals materials with respect to each other can lead to flat two-dimensional electronic bands which enables a wealth of physical phenomena. Here, we generalize this concept of so-called moiré flat bands to engineer flat bands in all three spatial dimensions controlled by the twist angle. The basic concept is to stack the material such that the large spatial moiré interference patterns are spatially shifted from one twisted layer to the next. We exemplify the general concept by considering graphitic systems, boron nitride, and WSe<sub>2</sub>, but the approach is applicable to any two-dimensional van der Waals material. For hexagonal boron nitride, we develop an <i>ab initio</i> fitted tight binding model that captures the corresponding three-dimensional low-energy electronic structure. We outline that interesting three-dimensional correlated phases of matter can be induced and controlled following this route, including quantum magnets and unconventional superconducting states.