Resonant Interlayer Coupling in NbSe<sub>2</sub>-Graphite Epitaxial Moiré Superlattices.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 41420360.
- Also identified by DOI 10.1002/adma.202511262 and PMC identifier 12902599.
- 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
Moiré heterostructures, created by stacking 2D materials together with a finite lattice mismatch or rotational twist, represent a new frontier of designer quantum materials. Typically, however, this requires the painstaking manual assembly of heterostructures formed from exfoliated materials. Here, clear spectroscopic signatures of moiré lattice formation in epitaxial heterostructures of monolayer (ML) NbSe<sub>2</sub> grown on graphite substrates are observed. Angle-resolved photoemission measurements and theoretical calculations of the resulting electronic structure reveal moiré replicas of the graphite π states forming pairs of interlocking Dirac cones. Interestingly, these intersect the NbSe<sub>2</sub> Fermi surface at the <math xmlns="http://www.w3.org/1998/Math/MathML"><semantics><mi>k</mi> <annotation>$k$</annotation></semantics> </math> -space locations where NbSe<sub>2</sub>'s charge-density wave (CDW) gap is maximal in the bulk. This provides a natural route to understand the lack of CDW enhancement for ML-NbSe<sub>2</sub>/graphene as compared to a more than fourfold enhancement for NbSe<sub>2</sub> on insulating support substrates, and opens new prospects for using moiré engineering for controlling the collective states of 2D materials.