Dirac Semimetal Heterostructures: 3D Cd3 As2 on 2D Graphene.
Yan-Fei Wu1,2, Liang Zhang3, Cai-Zhen Li3
1Institute for Quantum Science and Engineering and Department of Physics, South University of Science and Technology of China, Shenzhen, 518055, P. R. China.
Advanced Materials (Deerfield Beach, Fla.)
|July 12, 2018
Summary
Researchers created novel graphene-Cd3As2 heterostructures, demonstrating tunable electronic properties and enhanced nonlocal signals. This work advances van der Waals heterostructures for spintronics applications.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Quantum Materials
Background:
- Dirac semimetals are a significant class of quantum materials with 2D and 3D forms.
- 3D Dirac semimetals exhibit unique Fermi-arc surface states.
- 2D-3D Dirac van der Waals heterostructures offer potential for advanced electronics.
Purpose of the Study:
- To fabricate and investigate graphene-Cd3As2 heterostructures.
- To explore interlayer charge transfer and Fermi level modulation.
- To assess the potential for spintronics applications.
Main Methods:
- Direct layer-by-layer stacking of graphene and Cd3As2.
- Fabrication of planar graphene p-n-p junctions.
- Measurement of electronic transport properties, including nonlocal signals.
Main Results:
- Successful fabrication of graphene-Cd3As2 van der Waals heterostructures.
- Observation of significant interlayer charge transfer and Fermi level modulation in graphene.
- Demonstration of quantized conductance plateaus in p-n-p junctions.
- Enhanced nonlocal signals in hybrid devices due to spin-polarized surface states.
Conclusions:
- Graphene-Cd3As2 heterostructures exhibit tunable electronic properties.
- These heterostructures show promise for spintronics applications.
- The findings expand the scope of van der Waals heterostructures and Dirac semimetal research.
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