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Phase-shift control of the exchange coupling between magnetic impurities.
Jose d'Albuquerque E Castro1, Dora Altbir2, Alejandro O Leon3
1Universidade Federal do Rio de Janeiro Instituto de Fisica Caixa Postal 68528 BR-21 945 970 Rio de Janeiro, RJ Brazil.
Nanotechnology
|May 13, 2020
Summary
Electric potential barriers can control magnetic interactions in spintronics. This study demonstrates tuning the Ruderman-Kittel-Kasuya-Yosida (RKKY) coupling between magnetic impurities for applications in quantum computing.
Area of Science:
- Spintronics
- Condensed Matter Physics
- Quantum Computing
Background:
- Controlling magnetic interactions is crucial for spintronics applications.
- The Ruderman-Kittel-Kasuya-Yosida (RKKY) exchange coupling mediates interactions between magnetic impurities in electron systems.
- Developing methods to precisely tune RKKY coupling is an active area of research.
Purpose of the Study:
- To investigate the use of electric potential barriers to control RKKY exchange coupling.
- To explore the manipulation of both the magnitude and sign of RKKY coupling.
- To assess the feasibility of individually controlling magnetic interactions for advanced computing.
Main Methods:
- Theoretical modeling of magnetic impurities in a two-dimensional electron gas.
- Simulation of electric potential barriers to influence RKKY coupling.
- Analysis of systems with two and three magnetic impurities.
Main Results:
- Electric potential barriers effectively tune and suppress RKKY exchange coupling.
- Both the magnitude and sign of the RKKY coupling can be precisely manipulated.
- In three-impurity systems, two barriers can decouple one impurity from the others.
Conclusions:
- Electric potential barriers offer a viable method for controlling magnetic interactions at the atomic level.
- Individual control over magnetic interactions opens possibilities for novel spintronic devices.
- Potential applications include the development of neuromorphic and quantum computing architectures.
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