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Updated: Dec 30, 2025
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Scalable Quantum Integrated Circuits on Superconducting Two-Dimensional Electron Gas Platform
Published on: August 2, 2019
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Thermal quantum correlations in zigzag graphene nanoribbons.
Xiao-Dong Tan1,2, Qian-Hui Mao2
1School of Electronic Information and Electrical Engineering, Shangluo University, Shangluo 726000, People's Republic of China.
Summary
Entanglement in zigzag graphene nanoribbons (ZGNRs) is strongest between nearest edge spins and robust at room temperature. Multiparticle entanglement is also robust, suggesting ZGNRs are promising for quantum information processing.
Area of Science:
- Condensed Matter Physics
- Quantum Information Science
Background:
- Graphene nanoribbons (GNRs) exhibit unique electronic properties.
- Zigzag graphene nanoribbons (ZGNRs) possess edge states with potential for quantum applications.
Purpose of the Study:
- Investigate entanglement and quantum discord in ZGNRs.
- Explore the influence of temperature and ribbon width on these quantum correlations.
Main Methods:
- Utilized an effective spin-ladder model.
- Computed negativity and geometric quantum discord (GQD).
- Analyzed entanglement in two-spin and three-spin systems.
Main Results:
- Entanglement observed only in antiferromagnetically coupled edge spins.
- Dominant entanglement found in nearest inter-edge spin pairs, robust to temperature.
- Geometric quantum discord (GQD) is present in most edge pairs and depends on ribbon width.
- Multiparticle entanglement (ME) exists between spins on different edges and is more temperature-robust than two-spin entanglement.
Conclusions:
- Nearest inter-edge spin pairs in ZGNRs exhibit robust entanglement, ideal for quantum information processing.
- Multiparticle entanglement in ZGNRs offers enhanced thermal stability.
- ZGNRs show significant promise for developing quantum technologies.
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