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Giant Magnetization Modulation of Fe in Fe/Li3PO4 Heterostructures by Space Charge
Lihao Qin1, Zihao Miao1, Jia Yan1
1College of Physics, Qingdao University, Qingdao 266071, China.
ACS Applied Materials & Interfaces
|May 14, 2026
Summary
We demonstrate voltage control of magnetism in iron/lithium phosphate heterostructures using the space-charge effect. This method achieves significant magnetization changes at low voltages, showing potential for spintronic devices.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Nanotechnology
Background:
- Ferromagnetic metals are key for voltage control of magnetism (VCM) due to high Curie temperatures.
- The space-charge effect, separating electron and ion phases, enables magnetism modulation via spin-polarized electrons at surfaces.
Purpose of the Study:
- To fabricate and investigate Fe/Li3PO4 heterostructures for space-charge-mediated magnetism modulation.
- To explore the potential of polyanionic materials in electrically tunable magnetism.
Main Methods:
- Fabrication of Fe/Li3PO4 heterostructures via electrochemical reduction of LiFePO4 (LFP).
- Operando magnetometry to measure magnetization changes under applied voltage.
- Comprehensive analyses to demonstrate the dominance of the space-charge effect.
Main Results:
- A remarkable magnetization change of 56.6 emu gFe-1 was observed within a low voltage window (0.01-1.7 V).
- The modulation exhibited fast response and excellent cycling stability.
- The space-charge effect was confirmed as the dominant mechanism in the low voltage region.
Conclusions:
- Li3PO4's high ionic conductivity and interfacial stability are crucial for effective magnetism modulation.
- Polyanionic materials show significant potential for electrically tunable magnetism.
- This work offers a pathway for cost-effective, high-performance tunable spintronic devices.
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