Spin-transfer torque generated in graphene based topological insulator heterostructures.
Qingtian Zhang1, K S Chan2,3, Jingbo Li4
1School of Materials and Energy, Guangdong University of Technology, Guangzhou, Guangdong, 510006, People's Republic of China.
Scientific Reports
|March 14, 2018
Summary
We explored spin-transfer torque in graphene-based heterostructures. This novel approach offers efficient magnetic manipulation in spintronics without needing extra ferromagnetic layers, showing robustness against structural defects.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Spintronics
Background:
- Spin-transfer torque (STT) is crucial for magnetic device manipulation.
- Graphene-based heterostructures offer unique electronic properties.
- Topological insulators (TIs) exhibit quantum spin Hall effects.
Purpose of the Study:
- To investigate STT in normal-metal/topological-insulator/ferromagnet (N/TI/F) graphene heterostructures.
- To evaluate the potential of these structures for spintronic applications.
- To assess the robustness of STT against geometric variations.
Main Methods:
- Theoretical study of spin-transfer torque.
- Modeling of graphene-based N/TI/F heterostructures.
- Analysis of helical spin-polarized current effects.
Main Results:
- STT in N/TI/F structures is comparable to traditional ferromagnetic-normal-ferromagnetic junctions.
- The proposed structure avoids the need for an additional fixed magnetization ferromagnetic layer.
- STT demonstrates remarkable robustness against geometric imperfections like notches and nanopores.
Conclusions:
- Graphene-based quantum spin Hall insulators provide an efficient route for magnetization manipulation.
- The N/TI/F heterostructure is advantageous for spintronics due to its efficiency and robustness.
- This research paves the way for next-generation magnetic memory and logic devices.
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