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Updated: Jan 8, 2026
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Optimized Fabrication Procedure for High-Quality Graphene-based Moiré Superlattice Devices
Published on: July 11, 2025
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Resonant Interlayer Coupling in NbSe2-Graphite Epitaxial Moiré Superlattices
Shu Mo1, Ksenija Kovalenka2, Sebastian Buchberger1,3
1SUPA, School of Physics and Astronomy, University of St Andrews, St Andrews, KY16 9SS, UK.
Advanced Materials (Deerfield Beach, Fla.)
|December 20, 2025
Summary
Researchers observed moiré lattice formation in novel epitaxial heterostructures of monolayer niobium diselenide (NbSe2) on graphite. This finding offers new insights into controlling quantum material properties using moiré engineering.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Quantum Materials
Background:
- Moiré heterostructures are designer quantum materials formed by stacking 2D materials.
- Manual assembly of exfoliated materials is typically required.
- Epitaxial growth offers an alternative route to heterostructure fabrication.
Purpose of the Study:
- To investigate moiré lattice formation in epitaxial monolayer NbSe2 on graphite.
- To understand the electronic structure and collective state properties of these heterostructures.
- To explore prospects for moiré engineering in 2D materials.
Main Methods:
- Epitaxial growth of monolayer NbSe2 on graphite substrates.
- Angle-resolved photoemission spectroscopy (ARPES) measurements.
- Theoretical calculations of electronic structure.
Main Results:
- Observed clear spectroscopic signatures of moiré lattice formation.
- Revealed moiré replicas of graphite π states forming interlocking Dirac cones.
- Found Dirac cones intersecting the NbSe2 Fermi surface at maximal charge-density wave (CDW) gap locations.
Conclusions:
- The study provides a natural explanation for the lack of CDW enhancement in ML-NbSe2/graphene.
- Highlights the potential of moiré engineering for controlling collective states in 2D materials.
- Demonstrates the viability of epitaxial growth for creating moiré heterostructures.
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