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Abstract The Ruddlesden‐Popper 5diridate Sr2IrO4is an antiferromagnetic Mott insulator with the electronic, magnetic, and structural properties highly intertwined. Voltage control of its magnetic state is of intense fundmenatal and technological interest but remains to be demonstrated. Here, the tuning of magnetotransport properties in 5.2 nm Sr2IrO4via interfacial ferroelectric PbZr0.2Ti0.8O3is reported. The conductance of the epitaxial PbZr0.2Ti0.8O3/Sr2IrO4heterostructure exhibits ln(T) behavior that is characteristic of 2D correlated metal, in sharp contrast to the thermally activated behavior followed by 3D variable range hopping observed in single‐layer Sr2IrO4films. Switching PbZr0.2Ti0.8O3polarization induces nonvolatile, reversible resistance modulation in Sr2IrO4. At low temperatures, the in‐plane magnetoresisance in the heterostructure transitions from positive to negative at high magnetic fields, opposite to the field dependence in single‐layer Sr2IrO4. In the polarization down state, the out‐of‐plane anisotropic magnetoresistanceRAMRexhibits sinusoidal angular dependence, with a 90° phase shift below 20 K. For the polarization up state, unusual multi‐level resistance pinning appears inRAMRbelow 30 K, pointing to enhanced magnetocrystalline anisotropy. The work sheds new light on the intriguing interplay of interface lattice coupling, charge doping, magnetoelastic effect, and possible incipient ferromagnetism in Sr2IrO4, facilitating the functional design of its electronic and material properties.
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Role of crystalline and damping anisotropy to the angular dependences of spin rectification effect in single crystal CoFe film
Abstract The angular dependence of the microwave-driven spin rectification (SR) effect in single crystalline Co0.5Fe0.5alloy film is systematically investigated. Due to the strong current-orientation dependent anisotropic magnetoresistance (AMR), the SR effects in CoFe film strongly deviate from the ordinary sin 2φMcosφMrelation withφMdefined as the magnetization angle away from the current. A giant Gilbert damping anisotropy in the CoFe film with a maximum–minimum ratio of 520% is observed, which can impose a strong anisotropy onto magnetic susceptibility. The observed unusual angular dependence can be well explained by the theory including current-orientation dependent AMR and anisotropic magnetic susceptibility. Our work also suggests that the strong current-orientation dependent AMR in single crystalline CoFe film could exist up to the gigahertz frequency range.
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- PAR ID:
- 10303692
- Publisher / Repository:
- IOP Publishing
- Date Published:
- Journal Name:
- New Journal of Physics
- Volume:
- 22
- Issue:
- 9
- ISSN:
- 1367-2630
- Page Range / eLocation ID:
- Article No. 093047
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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