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Visualizing Uniaxial-strain Manipulation of Antiferromagnetic Domains in Fe1+YTe Using a Spin-polarized Scanning Tunneling Microscope
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Voltage-Controlled Antiferromagnetism in Magnetic Tunnel Junctions
Meng Xu1, Mingen Li2, Pravin Khanal1
1Department of Physics, University of Arizona, Tucson, Arizona 85721, USA.
Physical Review Letters
|May 23, 2020
Summary
We demonstrate voltage-controlled exchange bias in magnetic tunnel junctions. Electric fields can manipulate antiferromagnetic anisotropy, enabling sensitive detection of exchange bias effects.
Area of Science:
- Spintronics
- Materials Science
- Condensed Matter Physics
Background:
- Exchange bias is crucial for spintronic devices.
- Controlling exchange bias with electric fields is a key challenge.
- Interfacial effects significantly influence magnetic properties.
Purpose of the Study:
- To demonstrate voltage-controlled exchange bias in CoFeB/MgO/CoFeB magnetic tunnel junctions.
- To investigate the role of interfacial Fe(Co)Oₓ in this phenomenon.
- To explore electric field manipulation of antiferromagnetic anisotropy.
Main Methods:
- Fabrication of CoFeB/MgO/CoFeB magnetic tunnel junctions.
- Characterization of interfacial Fe(Co)Oₓ formation.
- Measurement of exchange bias field and tunneling magnetoresistance.
- Application of electric fields to the MgO barrier.
Main Results:
- Observed voltage-controlled exchange bias effect.
- Confirmed relation to interfacial Fe(Co)Oₓ.
- Demonstrated giant tunneling magnetoresistance and sharp switching.
- Showcased isothermal control of exchange bias by magnetic fields at low temperatures.
- Achieved effective manipulation of exchange bias via electric fields.
Conclusions:
- The study highlights a novel voltage-controlled exchange bias mechanism.
- Interfacial antiferromagnetism and voltage-controlled anisotropy are key.
- This system offers potential for sensitive detection and electric field control in spintronics.
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