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Updated: Jun 27, 2025
09:25
Fabricating van der Waals Heterostructures with Precise Rotational Alignment
Published on: July 5, 2019
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Tunneling current-controlled spin states in few-layer van der Waals magnets
ZhuangEn Fu1,2, Piumi I Samarawickrama1,2, John Ackerman3
1Department of Physics and Astronomy, University of Wyoming, Laramie, WY, 82071, USA.
Nature Communications
|May 1, 2024
Summary
Researchers used tunneling current to control spin states in chromium triiodide (CrI3) 2D magnets. This breakthrough enables tunable switching for advanced computing technologies.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Spintronics
Background:
- Controlling magnetic phases in 2D magnets is key for spintronics and future computing.
- Existing methods for spin control in 2D materials are limited.
Purpose of the Study:
- To explore the use of tunneling current for controlling spin states in 2D magnets.
- To investigate novel switching mechanisms beyond conventional bi-stable systems.
Main Methods:
- Fabrication of few-layer CrI3 devices with graphene electrodes.
- Application of controlled tunneling currents (polarity and amplitude).
- Analysis of spin-state switching and stochastic behavior.
Main Results:
- Deterministic switching between spin-parallel and spin-antiparallel states in CrI3 using tunneling current.
- Demonstration of tunneling current-tunable stochastic switching between multiple spin states.
- Proposed mechanism involving nonequilibrium spin accumulation in graphene electrodes.
Conclusions:
- Tunneling current offers a novel and effective method for controlling magnetism in 2D materials.
- The observed multi-state stochastic switching opens new avenues for probabilistic and neuromorphic computing.
- Findings address a critical knowledge gap in 2D magnet spintronics.
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