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Abstract Unidirectional magnetoresistance (UMR) has been observed in a variety of stacks with ferromagnetic/spin Hall material bilayer structures. In this work, UMR in antiferromagnetic insulator Fe2O3/Pt structure is reported. The UMR has a negative value, which is related to interfacial Rashba coupling and band splitting. Thickness‐dependent measurement reveals a potential competition between UMR and the unidirectional spin Hall magnetoresistance (USMR). This work reveals the existence of UMR in antiferromagnetic insulators/heavy metal bilayers and broadens the way for the application of antiferromagnet‐based spintronic devices.
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This content will become publicly available on January 1, 2027
Lithium and Vanadium Intercalation into Bilayer V 2 Se 2 O: Ferrimagnetic–Ferroelastic Multiferroics and Anomalous and Spin Transport
Abstract Spin splitting in emerging altermagnets is nonrelativistic and momentum dependent, yet energy independent, and localized in momentum space, posing challenges for practical applications. Here, an intercalation‐driven paradigm is proposed for altermagnets to attain ameliorative electronic structures, multiferroic characteristics, and anomalous and spin transport functionalities. As a representative system, electrochemistry‐ and self‐intercalated V2Se2O bilayers are investigated, building on the recently reported room‐temperature K‐ and Rb‐intercalated V2Se2O family, utilizing density functional theory, Wannier function analyses, Monte Carlo simulations, and nonequilibrium Green's function methods. Intercalation induces room‐temperature intralayer ferrimagnetic and interlayer ferromagnetic orders (358 K for Li intercalation and 773 K for V intercalation), ferroelasticity (≈1% signal intensity), in‐plane uniaxial magnetic anisotropy, and metallization, while also modifying the anomalous Hall effect. Notably, Li‐ and V‐intercalated V2Se2O bilayers exhibit enhanced spin splitting and half‐metallic behavior, respectively, yielding near‐perfect spin filtering efficiency. Intercalation substantially enhances spin transport in V2Se2O‐based devices, enabling giant magnetoresistance (877%), ultrahigh thermal tunneling magnetoresistance (≈12 000%), and observable spin Seebeck and temperature negative differential resistance effects. This intercalation‐driven paradigm expands altermagnetic functionalities through multifunctional integration, offering promising avenues for advanced, miniaturized, room‐temperature exploitation of anomalous, electron, and spin transport properties.
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- Award ID(s):
- 2145074
- PAR ID:
- 10677610
- Publisher / Repository:
- Advanced Science
- Date Published:
- Journal Name:
- Advanced Science
- Volume:
- 13
- Issue:
- 5
- ISSN:
- 2198-3844
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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