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Updated: Jun 3, 2026
10:36
Advanced Experimental Methods for Low-temperature Magnetotransport Measurement of Novel Materials
Published on: January 21, 2016
Electronic transport through a graphene-based ferromagnetic/normal/ferromagnetic junction
Jiang-chai Chen1, Shu-guang Cheng, Shun-qing Shen
1Beijing National Lab for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, People's Republic of China.
Summary
This study explores graphene spin valves, finding 100% magnetoresistance (MR) in zigzag edge structures. Narrower ribbons and specific Fermi energies enhance this effect, crucial for spintronic device development.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Spintronics
Background:
- Graphene's unique electronic properties make it a promising material for spintronic devices.
- Understanding spin-dependent transport in magnetic junctions is key to developing advanced electronics.
Purpose of the Study:
- Investigate electronic transport in graphene-based ferromagnetic/normal/ferromagnetic junctions.
- Determine the conditions for achieving high magnetoresistance (MR) in such systems.
- Evaluate the impact of structural parameters and disorder on MR performance.
Main Methods:
- Utilized the Landauer-Büttiker formalism for transport calculations.
- Employed the nonequilibrium Green function technique for theoretical analysis.
- Simulated transport properties across graphene ribbons with varying edge types (zigzag and armchair).
Main Results:
- Achieved 100% magnetoresistance (MR) plateaus in zigzag edge graphene junctions at specific Fermi energies.
- Demonstrated that narrower graphene ribbons and lead magnetization alignment significantly influence MR.
- Observed reduced but still substantial MR (around 50%) in the presence of disorder.
Conclusions:
- Zigzag edge graphene ribbons are highly favorable for fabricating efficient graphene-based spin valve devices.
- The band-selective rule in zigzag edges enables near-perfect spin filtering and high MR.
- Graphene spin valves offer potential for high-performance spintronic applications, robust even with some disorder.
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