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Updated: Oct 4, 2025
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Published on: July 11, 2025
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Quantum interference and domain-wall-like magnetic correlations in hexagonal graphene nanodisks
Dong-Sheng Hu1, Ling-Ling Ma2, Shi-Chang Xiao3
1College of Science, Nanjing University of Aeronautics and Astronautics, Nanjing 211106, People's Republic of China.
Summary
We discovered that quantum interference and domain wall effects simultaneously control magnetism in graphene nanodisks. This finding offers a new method for engineering magnetism in graphene nanostructures for spintronics applications.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Nanotechnology
Background:
- Magnetism in materials is typically manipulated via quantum interference or domain wall effects.
- Graphene nanostructures offer unique platforms for exploring novel magnetic phenomena.
Purpose of the Study:
- To investigate the simultaneous emergence of quantum interference and domain wall effects in designed graphene nanodisks.
- To explore methods for engineering magnetism in graphene nanostructures.
Main Methods:
- Numerical simulations were employed to study magnetic properties of hexagonal graphene nanodisks.
- The influence of edge geometry, specifically armchair edge length, on magnetic behavior was analyzed.
Main Results:
- Quantum interference effects, similar to those in graphene nanoribbons, were found to robustly determine magnetic structure in small nanodisks.
- A domain-wall-like magnetic mechanism was identified as dominant in larger graphene nanodisks.
- A magnetic state with fully spin-polarized edges was achieved across a broad parameter range.
Conclusions:
- Graphene nanodisks exhibit a dual mechanism for magnetic manipulation, combining quantum interference and domain wall effects.
- The ability to engineer spin-polarized edges in graphene nanostructures opens avenues for spintronics applications.
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