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Voltage-Driven All-Solid-State Ionic Control on Co/CoO Antiferromagnet/Ferromagnet Exchange Bias.
Gabriel Vinicius de Oliveira Silva1,2, Labanya Ghosh1,2, Rabiul Islam1,2
1Department of Electrical and Computer Engineering, University of Waterloo, Waterloo, Ontario N2L 3G1, Canada.
ACS Nano
|May 28, 2025
Summary
Voltage-driven ion transport in a Co/CoO heterostructure efficiently controls magnetism in spintronic devices. This magneto-ionic approach offers reversible magnetic switching with low energy costs, enabling advanced applications.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Nanotechnology
Background:
- Spintronics traditionally uses high electric currents, leading to energy dissipation.
- Voltage control of magnetism (VCM) offers a low-energy alternative.
- Magneto-ionics utilizes voltage-driven ion transport for energy-efficient magnetic control.
Purpose of the Study:
- To demonstrate voltage-driven ionic control of CoO antiferromagnetism.
- To manipulate magnetic properties in exchange-coupled ferromagnetic Cobalt (Co).
- To explore an energy-efficient VCM approach for spintronic applications.
Main Methods:
- Fabrication of a Co/CoO heterostructure using a "battery-like" device geometry.
- Utilizing a solid-state electrolyte and a lithium (Li) ion source.
- Applying gate biases to induce reversible CoO layer conversion and measuring anisotropic magnetoresistance (AMR).
Main Results:
- Reversible conversion between Co and CoO in the cathode layer, sustained over 1000 cycles.
- Voltage-induced ionic control of CoO antiferromagnetism.
- Manipulation of magnetic properties in the exchange-coupled ferromagnetic Co layer, evidenced by AMR.
Conclusions:
- Demonstrated an efficient, all-solid-state, voltage-driven, and highly reversible ionic control method.
- The magneto-ionic approach offers new dimensions of control for spintronic devices.
- Potential for mass integration of voltage-controlled magnetic channels in future spintronics.
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