Related Experiment Video
Updated: Feb 19, 2026
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Visualizing Uniaxial-strain Manipulation of Antiferromagnetic Domains in Fe1+YTe Using a Spin-polarized Scanning Tunneling Microscope
Published on: March 24, 2019
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Spin-transfer torque in multiferroic tunnel junctions with composite dielectric/ferroelectric barriers
Julian P Velev1,2,3, Pablo Merodio1, Cesar Pollack1
1Department of Physics and Astronomy, University of Puerto Rico, San Juan, PR 00931, United States of America.
Summary
Electric fields offer high control over spin-transfer torque (STT) in multiferroic tunnel junctions. Polarization switching can tune STT, enabling novel functionalities for magnetic memories and sensors.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Spintronics
Background:
- Multiferroic tunnel junctions (MTJs) offer tunable magnetic properties.
- Spin-transfer torque (STT) is crucial for magnetic memory device operation.
- Controlling STT via electric fields is highly desirable for energy-efficient spintronics.
Purpose of the Study:
- To investigate the electric field control of STT in MTJs with composite dielectric/ferroelectric barriers.
- To explore the polarization-tunability of both voltage-induced and zero-voltage STT.
- To identify potential applications for engineered STT in advanced memory and logic devices.
Main Methods:
- Utilizing theoretical model calculations.
- Analyzing MTJs with composite dielectric/ferroelectric barriers.
- Simulating the effects of electric field and polarization reversal on STT.
Main Results:
- Demonstrated high-level electric field control over STT.
- Showcased the ability to quench/release voltage-induced STT by toggling polarization.
- Revealed sign switching of zero-voltage STT (interlayer exchange coupling) with polarization reversal.
Conclusions:
- Electric field and polarization offer significant tunability of STT in MTJs.
- This tunability can be exploited for novel functionalities like bit softening/hardening and enhanced sensor performance.
- Potential implications for advanced magnetic random access memories and combined memory/logic devices.
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