Two-Dimensional Metal-Organic Framework on Superconducting NbSe₂.

Area of Science:

• Materials Science
• Condensed Matter Physics
• Quantum Materials

Background:

• Vertical heterostructures of 2D materials offer a route to designer quantum materials.
• 2D metal-organic frameworks (MOFs) provide flexibility for creating designer heterostructures.

Purpose of the Study:

• To fabricate and characterize a monolayer 2D MOF on a 2D van der Waals superconducting substrate.
• To explore the electronic properties and band structure formation in this novel heterostructure.

Main Methods:

• Fabrication of a monolayer 2D Cu-dicyanoanthracene MOF on a NbSe2 substrate.
• Low-temperature scanning tunneling microscopy (STM) and spectroscopy (STS) for characterization.
• Density-functional theory (DFT) calculations to complement experimental findings.

Main Results:

• Successful synthesis of a 2D MOF on a superconducting substrate.
• Characterization of two distinct phases of the 2D MOF.
• Observation of kagome band structure formation from Star of David building blocks.

Conclusions:

• This work extends 2D MOF synthesis to superconducting substrates, crucial for quantum materials.
• Enables electronic tunability of 2D MOFs for applications in topological superconductivity.
• Paves the way for developing novel quantum materials with exotic properties.