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Continuous Room-Temperature Spin-Injection Modulation Achieved by Spin-Filtering Competition in Molecular Spin Valves
Shunhua Hu1,2, Wei Liu2,3, Lidan Guo1
1Key Laboratory of Nanosystem and Hierarchical Fabrication, National Center for Nanoscience and Technology, Beijing, 100190, P. R. China.
Advanced Materials (Deerfield Beach, Fla.)
|April 6, 2023
Summary
Researchers developed a new spin-filtering-competition mechanism to control interfacial effects in molecular spin valves. This breakthrough allows for precise modulation of spin injection and magnetoresistance at room temperature.
Area of Science:
- Spintronics
- Materials Science
- Interface Physics
Background:
- Spin-related phenomena at ferromagnetic/molecular semiconductor interfaces are key to spintronics.
- Precise control of interfacial effects, especially at room temperature, remains a significant challenge for molecular spintronics development.
Purpose of the Study:
- To propose and demonstrate an innovative spin-filtering-competition mechanism for continuous modulation of interfacial effects.
- To achieve steady and predictable spintronic functionalities at room temperature.
Main Methods:
- Investigated the competition between intrinsic spin-filtering effects of cobalt and a new effect induced by cobalt-lithium fluoride bonding.
- Controlled the spin-injection process by precisely adjusting lithium fluoride coverage on the cobalt surface.
Main Results:
- Successfully demonstrated continuous modulation of interfacial effects in molecular spin valves at room temperature.
- Achieved active control over spin polarization and magnetoresistance, including sign reversal.
Conclusions:
- The proposed spin-filtering-competition mechanism offers an innovative approach for precise control of spin-related interfacial effects.
- This work may significantly advance the scientific and technological development of molecular spintronics.
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