Journal of Magnetism and Magnetic Materials最新文献_第6页

Twist-tunable moiré magneto-Excitonic Polaritons at 2D ferromagnetic interfaces 二维铁磁界面上的扭可调谐磁激子

IF 3 3区材料科学 Q3 MATERIALS SCIENCE, MULTIDISCIPLINARY

Journal of Magnetism and Magnetic Materials

Pub Date : 2026-01-06 DOI: 10.1016/j.jmmm.2026.173812

Arash Vaghef-Koodehi , Mahmoud Nikoufard , Yaser Bahari

We present a theoretical investigation of moiré magneto-excitonic polaritons in twisted bilayer transition-metal dichalcogenide heterostructures interfaced with two-dimensional ferromagnets. By combining a full electromagnetic simulation based on time-domain finite-difference (FDTD) calculations with a microscopic exciton–magnon Hamiltonian derived from tight-binding theory, we reveal the emergence of strong hybridization between excitonic and magnonic modes mediated by the moiré superlattice potential. The coupling strength exhibits Rabi splitting up to ≈ 8 meV under moderate magnetic fields and maintains coherent hybridization up to 180 K for CrI₃ and 230 K for Fe₃GeTe₂ substrates. The hybrid mode shows pronounced valley-selective behavior with an intensity ratio of ∼8:1 (K:K′) and an ultrafast oscillation period in the terahertz (THz) range, corresponding to light–matter–spin coherence on the picosecond scale. These results uncover a controllable pathway to engineer moiré-assisted exciton–magnon coupling governed by twist angle, magnetic exchange, and gate bias, thereby providing a physical foundation for tunable spin-polarized quantum photonic and opto-magnonic devices. Beyond its fundamental implications for correlated moiré physics, this study delineates a realistic route toward THz-bandwidth, nonreciprocal, and valley-selective photonic interfaces operating at elevated temperatures—establishing moiré magneto-excitonics as a credible frontier for next-generation hybrid quantum materials.

我们提出了二维铁磁体界面的扭曲双层过渡金属双硫化物异质结构中moirir磁激子的理论研究。通过将基于时域有限差分（FDTD）计算的完整电磁模拟与由紧密结合理论推导的微观激子-磁振子哈密顿量相结合，我们揭示了由莫尔超晶格势介导的激子模式和磁振子模式之间强杂化的出现。耦合强度在中等磁场下显示出高达≈8 meV的Rabi分裂，并且在CrI₃和Fe₃GeTe₂衬底上保持高达180 K和230 K的相干杂化。混合模式显示出明显的谷选择行为，强度比为~ 8:1 （K:K’），在太赫兹（THz）范围内具有超快振荡周期，对应于皮秒尺度的光-物质自旋相干。这些结果揭示了一种可控的途径来设计由扭曲角、磁交换和栅极偏置控制的莫尔梅兹辅助激子-磁振子耦合，从而为可调谐自旋极化量子光子和光磁振子器件提供了物理基础。除了相关莫尔莫尔物理学的基本含义之外，本研究还描绘了在高温下工作的太赫兹带宽，非互反和谷选择性光子界面的现实路线-将莫尔莫尔磁激子学建立为下一代混合量子材料的可靠前沿。

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引用次数: 0

Probing the local atomic structure and magnetism in Iron and manganese co-doped indium oxide Nanocubes using XAS and DFT 利用XAS和DFT探测铁锰共掺杂氧化铟纳米立方的局部原子结构和磁性

IF 3 3区材料科学 Q3 MATERIALS SCIENCE, MULTIDISCIPLINARY

Journal of Magnetism and Magnetic Materials

Pub Date : 2026-01-06 DOI: 10.1016/j.jmmm.2026.173814

Manikandan Dhamodaran , Rahul Kumar Yadav , N. Raja , Ramesh Karuppannan , Rajeev Gupta

We examine the impact of iron and manganese co-doping on the local atomic environment in hydrothermally synthesized In₂O₃ using synchrotron X-ray absorption spectroscopy analysis, correlating the findings with the observed magnetic properties. The results revealed that manganese is mainly present in the +3-valence state with a dilute contribution from the +4 state. These oxidation states indicate the formation of oxygen vacancies resulting from charge imbalance. The effective co-substitution of iron and manganese atoms in the In₂O₃ was established, accompanied by specific changes in bond lengths. Additionally, the bond length of MnO slightly increased for In_1.94Fe_0.02Mn_0.04O₃, and subsequently, decreased for the higher Mn-doped samples. Density functional theory calculations revealed that the FeO bond length decreases from 2.194 to 2.141 Å upon the introduction of oxygen vacancies, indicating enhanced FeO interactions. Conversely, the MnO bond increased from 2.140 to 2.210 Å, reflecting the weakened local bonding environment and reduced lattice integration of Mn atoms. Magnetic investigations revealed a room-temperature ferromagnetism in In_1.94Fe_0.02Mn_0.04O₃, characterized by an enhanced coercivity and saturation magnetization. Density functional theory calculations show that oxygen vacancy formation stabilizes the high magnetic moments 3.85 μ_B for Fe and 4.23 μ_B for Mn, driven by FeO and MnO hybridization and increased d-electron localization around the transition metal centers. These findings offer new insights into the local micro-environment and magnetic characteristics of iron and manganese-codoped indium oxide.

我们利用同步x射线吸收光谱分析研究了铁和锰共掺杂对水热合成In2O3中局部原子环境的影响，并将这些发现与观察到的磁性能联系起来。结果表明，锰主要以+3价态存在，+4价态的贡献较小。这些氧化态表明由于电荷不平衡而形成的氧空位。在In2O3中建立了铁和锰原子的有效共取代，并伴随着键长的特定变化。此外，在In1.94Fe0.02Mn0.04O3中，MnO的键长略有增加，随后在mn掺杂较高的样品中，MnO的键长减小。密度泛函理论计算表明，引入氧空位后，FeO键长从2.194减小到2.141 Å，表明FeO相互作用增强。相反，MnO键从2.140增加到2.210 Å，反映了局部键合环境的减弱和Mn原子晶格积分的降低。磁学研究表明，In1.94Fe0.02Mn0.04O3具有室温铁磁性，具有增强的矫顽力和饱和磁化。密度泛函理论计算表明，氧空位的形成稳定了Fe （3.85 μB）和Mn （4.23 μB）的高磁矩，这是由FeO和MnO杂化和过渡金属中心周围d电子局域化的增加所驱动的。这些发现为铁锰共掺杂氧化铟的局部微环境和磁性特性提供了新的见解。

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引用次数: 0

Effect of Dy and Tb addition on the structural, thermal and magnetic properties of Nd33Fe67 melt spun alloys 添加Dy和Tb对Nd33Fe67熔体纺丝合金组织、热、磁性能的影响

IF 3 3区材料科学 Q3 MATERIALS SCIENCE, MULTIDISCIPLINARY

Journal of Magnetism and Magnetic Materials

Pub Date : 2026-01-03 DOI: 10.1016/j.jmmm.2025.173797

S. Naveen Rajkumar , Akshaya Senthilkumar , D. Arvindha Babu , M. Manivel Raja , Elangovan Hemaprabha

In this study, the effect of Dy and Tb addition on structural, thermal and magnetic properties of Nd₃₃Fe₆₇ melt spun ribbons was studied with an aim to stabilize Nd₅Fe₁₇ phase and increase coercivity. Dy and Tb addition led to the formation of partial amorphous phase along with crystalline phases of Nd₂Fe₁₇ and Nd(Fe) solid solution phases at low concentrations (up to Dy = Tb = 4 at.%) and DyFe₂/TbFe₂ phases also form beyond Dy = Tb = 6 at.%. While annealing at 350 °C results in partial formation of the equilibrium Nd₅Fe₁₇ phase along with other existing phases i.e. amorphous, Nd₂Fe₁₇ and Nd(Fe) solid solution, annealing at 670 °C results in only equilibrium Nd₅Fe₁₇, Nd(Fe) solid solution, and DyFe₂/TbFe₂ phases. The Curie temperature of amorphous phase increases with increasing Dy/Tb content for low concentration of Dy/Tb and it decreases for high Dy/Tb concentration. Presence of Dy/Tb atoms in the amorphous phase causes FeFe distance to change and influences the exchange interaction thereby affecting the Curie temperature. Presence of amorphous phase having large random anisotropy, Nd₂Fe₁₇ phase having high anisotropy and DyFe₂/TbFe₂ having high anisotropy in Dy/Tb added as spun alloys result in increased coercivity as compared to the alloy having no Dy/Tb. Annealing at 350 °C showed a trend of increasing coercivity with Dy/Tb due to the presence of three hard magnetic phases i.e. amorphous, Nd₂Fe₁₇ and DyFe₂/TbFe₂ phases along with soft magnetic Nd₅Fe₁₇ phase. Annealing at 670 °C resulted in the formation of soft magnetic Nd₅Fe₁₇ phase along with hard magnetic DyFe₂/TbFe₂ phases which showed lowest coercivity observed across all alloys. Dy/Tb addition decreases magnetization in all samples due to their anti-parallel interaction with the amorphous matrix and the ferrimagnetic contribution of DyFe₂/TbFe₂ phases.

本研究以稳定Nd5Fe17相和提高矫顽力为目的，研究了添加Dy和Tb对Nd33Fe67熔体纺带结构、热、磁性能的影响。在低浓度（Dy = Tb = 4 at）下，添加Dy和Tb可形成Nd2Fe17的部分非晶相和Nd（Fe）固溶体相。%)和DyFe2/TbFe2相也在Dy = Tb = 6at .%以上形成。在350℃退火时，部分形成Nd5Fe17平衡相以及其他相，即非晶相、Nd2Fe17和Nd（Fe）固溶体，而在670℃退火时，只形成Nd5Fe17、Nd（Fe）固溶体和DyFe2/TbFe2平衡相。低Dy/Tb浓度时，非晶相居里温度随Dy/Tb含量的增加而升高，高Dy/Tb浓度时居里温度降低。在非晶相中存在Dy/Tb原子，使FeFe距离发生变化，影响交换作用，从而影响居里温度。与不添加Dy/Tb的合金相比，添加Dy/Tb的合金中存在具有大随机各向异性的非晶态相、具有高各向异性的Nd2Fe17相和具有高各向异性的DyFe2/TbFe2相，使得矫顽力增加。在350℃退火时，由于存在三种硬磁相，即非晶相、Nd2Fe17相和DyFe2/TbFe2相以及软磁相Nd5Fe17，合金的矫顽力随Dy/Tb的增加而增加。670℃退火形成软磁Nd5Fe17相和硬磁DyFe2/TbFe2相，其矫顽力在所有合金中最低。由于Dy/Tb与非晶基体的反平行相互作用以及DyFe2/TbFe2相的铁磁贡献，使得所有样品的磁化强度都降低。

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引用次数: 0

Magnetic carbon-nanoparticles behavior of biomorphic pyrolytic carbons 磁性碳纳米颗粒的生物形态热解碳行为

IF 3 3区材料科学 Q3 MATERIALS SCIENCE, MULTIDISCIPLINARY

Journal of Magnetism and Magnetic Materials

Pub Date : 2026-01-02 DOI: 10.1016/j.jmmm.2026.173811

V.V. Popov , T.S. Orlova , A.A. Spitsyn , D.A. Kirilenko , K.V. Dyakonov

Magnetic properties of biomorphic carbon-based materials obtained from birch-wood pyrolysis products using carbonization temperature of 700 °C with and without subsequent activation at 970 °C have been studied in a wide temperature range of 2–300 K in magnetic fields up to 140 kOe. It was found that biocarbon samples purified from volatile wood decomposition product (tar) during pyrolysis demonstrate diamagnetic behavior of magnetization at room temperature and paramagnetic at low temperatures, while in biocarbon samples with residual or specially introduced pyrolysis tar, a ferromagnetic component of magnetization is observed at room temperature. The analysis showed that ferromagnetism appears as a result of the formation of carbon magnetic nanoparticles during the carbonization of binding tar in the biocarbon. The magnitude of magnetization of such nanoparticles is comparable to the magnetization of nanoparticles formed by ferromagnetic metals that opens way to obtain porous magnetic biocarbon materials without ferromagnetic metal inclusions.

在高达140 kOe的磁场中，在2-300 K的宽温度范围内，研究了在700°C炭化温度下，经过970°C活化和不经过活化的桦木热解产物的生物形态碳基材料的磁性能。研究发现，热解过程中挥发性木材分解产物（焦油）纯化的生物碳样品在室温下表现出抗磁性磁化行为，在低温下表现出顺磁性，而在残余或特别引入热解焦油的生物碳样品中，在室温下表现出铁磁性磁化成分。分析表明，铁磁性是生物炭中结合焦油碳化过程中碳磁性纳米颗粒形成的结果。这种纳米颗粒的磁化强度与铁磁性金属形成的纳米颗粒的磁化强度相当，为获得没有铁磁性金属内含物的多孔磁性生物碳材料开辟了道路。

引用次数: 0

Grain-orientation engineering enables dual-functionality in (Mn,Fe)2(P,Si)/epoxy composites: Colossal negative thermal expansion and anisotropic magnetocaloric effect 晶粒取向工程使（Mn,Fe）2(P,Si)/环氧复合材料具有双重功能：巨大的负热膨胀和各向异性磁热效应

IF 3 3区材料科学 Q3 MATERIALS SCIENCE, MULTIDISCIPLINARY

Journal of Magnetism and Magnetic Materials

Pub Date : 2026-01-02 DOI: 10.1016/j.jmmm.2025.173809

Yong Gong , Zhubing Yan , Francesco Cugini , Fengjiao Qian , Jiawei Lai , Xuefei Miao , Jun Liu , Zhixiang Qi , Yuanyuan Gong , Feng Xu , Luana Caron

The 〈001〉 − oriented (Mn,Fe)₂(P,Si)/epoxy composites were fabricated via magnetic field-assisted dynamic self-assembly. These textured composites demonstrate remarkable adaptability for diverse applications that require either substantial coefficients (α_l) of negative thermal expansion (NTE) or broad NTE temperature windows (ΔT_NTE). A two-dimensional NTE with a colossal α_l of −144.37 × 10⁻⁶ K⁻¹ is realized between 280 and 360 K in the composite displaying a first-order phase transition (FOPT). The ΔT_NTE can be significantly extended to 190 K (120−310K) in the composite exhibiting a second-order phase transition (SOPT), while preserving a large α_l of −23.89 × 10⁻⁶ K⁻¹. Besides that, anisotropic MCE is observed in the textured composites. The FOPT composite exhibits a maximum entropy change of 7.18 Jkg⁻¹ K⁻¹ under a magnetic field of 1 T applied perpendicular to the texture direction, which is 34 % higher than the parallel field configuration. Consequently, our study demonstrates that grain-orientation engineering can be effectively employed to explore NTE and achieve anisotropic magnetocaloric properties.

采用磁场辅助动态自组装法制备了< 001 >−取向（Mn,Fe）2(P,Si)/环氧复合材料。这些纹理复合材料表现出卓越的适应性，适用于需要大量负热膨胀（NTE）系数（αl）或宽NTE温度窗（ΔTNTE）的各种应用。在280 ~ 360 K范围内实现了αl为−144.37 × 10−6 K−1的二维NTE，显示了一阶相变（FOPT）。在复合材料中，ΔTNTE可以明显扩展到190 K (120 ~ 310K)，表现出二级相变（SOPT），同时保持了较大的αl （- 23.89 × 10 ~ 6 K−1）。此外，在织构复合材料中观察到各向异性的MCE。在垂直于织构方向的1 T磁场下，FOPT复合材料的最大熵变为7.18 Jkg−1 K−1，比平行磁场配置高34%。因此，我们的研究表明，晶粒取向工程可以有效地用于探索NTE并获得各向异性磁热性能。

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引用次数: 0

Tunneling magnetoresistance anomalies in a single-molecule magnet spin valve 单分子磁体自旋阀的隧穿磁阻异常

IF 3 3区材料科学 Q3 MATERIALS SCIENCE, MULTIDISCIPLINARY

Journal of Magnetism and Magnetic Materials

Pub Date : 2025-12-31 DOI: 10.1016/j.jmmm.2025.173795

Zhengzhong Zhang , Han Hu , Runze Zhu , Yanzong Wang , Hao Liu

We theoretically investigate the inelastic electron transport process in a molecular spin-valve, which consists of a single-molecule magnet weakly coupled between a pair of ferromagnetic electrodes. Owing to the influence of the spin moment of the molecule on itinerant electrons, the tunneling magnetoresistance of this device exhibits two distinct phenomena: when the molecular magnetism is parallel to that of both FM electrodes, the magnetoresistance is enhanced; otherwise, it is suppressed, leading to a negative magnetoresistance phenomenon. We discuss the analytical expression of magnetoresistance under low temperature condition and find that both types of phenomena depend mainly on the spin polarization of the ferromagnetic electrodes. Based on the intrinsic magnetism of molecule, these two types of magnetoresistance can be prepared, preserved and detected under near zero magnetic field conditions. This molecular electrical device can be realized with current technologies and may have practical use in magnetic structures combined with molecular magnets, such as magnetic molecular spin-valve structures.

我们从理论上研究了分子自旋阀中的非弹性电子输运过程，该自旋阀由一对铁磁电极之间弱耦合的单分子磁体组成。由于分子的自旋力矩对流动电子的影响，该器件的隧穿磁阻表现出两种明显的现象：当分子的磁性与两个调频电极的磁性平行时，磁阻增强；否则，它被抑制，导致负磁阻现象。讨论了低温条件下磁电阻的解析表达式，发现这两种现象主要取决于铁磁电极的自旋极化。基于分子的本征磁性，这两种磁电阻可以在近零磁场条件下制备、保存和检测。这种分子电装置可以用现有的技术实现，在磁性分子自旋阀结构等与分子磁体结合的磁性结构中具有实际应用价值。

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引用次数: 0

Phase stability and tunable structural, hyperfine, and magnetic properties of Sol–Gel FeNi nanoparticles 溶胶-凝胶FeNi纳米颗粒的相稳定性和可调结构、超细和磁性能

IF 3 3区材料科学 Q3 MATERIALS SCIENCE, MULTIDISCIPLINARY

Journal of Magnetism and Magnetic Materials

Pub Date : 2025-12-30 DOI: 10.1016/j.jmmm.2025.173792

M.A.R. Martinez , F.F.H. Aragón , L. León Félix , J. Mantilla , M.H. Sousa , M.C. Mathpal , J.F. Felix , J.A.H. Coaquira

In this study,

\sim

Fe₅₀Ni₅₀ powder alloys were synthesized successfully using the sol–gel method, followed by systematic thermal treatments up to 1000 °C in a reducing atmosphere (Ar-H

_{2}

). Synchrotron X-ray diffraction patterns indicate that the data are well modeled by face-centered cubic (FCC) FeNi phase. The stability of this phase was studied, revealing that as the temperature is increased, the unit cell volume changes, suggesting an enhancement in the migration of iron atoms. This migration alters the stoichiometry of the FeNi alloy, potentially shifting it beyond its nominal 50/50 composition. High-resolution TEM demonstrated the formation of the FeNi phase, which is in good agreement with the results obtained by XRD. Additionally, only a slight increase in crystalline particle size was observed. Magnetic characterization shows that thermal annealing strongly influences the magnetization. In particular, the sample annealed at 700 °C exhibits the highest magnetization and a Curie temperature

\sim

805 K, highlighting the role of thermal treatments in tuning the magnetic response. Zero-field cooling and field cooling measurements in the range 5–380 K further reveal irreversibilities above room temperature, attributed to the small particle size and strong interparticle interactions, which significantly affect the coercive field and overall magnetic behavior. These FeNi nanoparticles were characterized as magnetically soft materials. Mössbauer spectroscopy confirms the ferromagnetic behavior of the cubic FeNi phase as shown by XRD. Increasing the treatment temperature produces an increase in the hyperfine magnetic field, while the IS becomes more negative, which is primarily attributed to modifications in the s-electron density at the iron nuclei resulting from thermally induced electronic redistribution.

在本研究中，采用溶胶-凝胶法成功合成了~ Fe50Ni50粉末合金，然后在还原气氛（Ar-H2）中进行了高达1000°C的系统热处理。同步加速器x射线衍射图表明，面心立方（FCC） FeNi相能很好地模拟数据。研究了该相的稳定性，发现随着温度的升高，单位胞体积发生变化，表明铁原子的迁移增强。这种迁移改变了FeNi合金的化学计量，可能使其超出其标称的50/50组成。高分辨率透射电镜显示FeNi相的形成，这与XRD的结果吻合较好。此外，仅观察到晶体粒度略有增加。磁性表征表明，热退火对磁化强度有较大影响。特别是，在700°C退火的样品表现出最高的磁化强度和居里温度~ 805 K，突出了热处理在调节磁响应中的作用。在5-380 K范围内的零场冷却和场冷却测量进一步揭示了室温以上的不可逆性，这归因于小颗粒尺寸和强颗粒间相互作用，这显著影响了矫顽力场和整体磁行为。这些FeNi纳米颗粒被表征为磁性软材料。Mössbauer光谱分析证实了立方FeNi相的铁磁行为，如XRD所示。随着处理温度的升高，超细磁场增大，而IS变得更负，这主要是由于热诱导电子重分布导致铁核s电子密度的改变。

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引用次数: 0

Piezoelectric strain influenced modulation of magnetic domain wall motion in hybrid PMN-PT (011)/CoFeB heterostructures with perpendicular magnetic anisotropy 压电应变对垂直磁各向异性PMN-PT (011)/CoFeB杂化异质结构磁畴壁运动调制的影响

IF 3 3区材料科学 Q3 MATERIALS SCIENCE, MULTIDISCIPLINARY

Journal of Magnetism and Magnetic Materials

Pub Date : 2025-12-30 DOI: 10.1016/j.jmmm.2025.173796

S. Roy , A. Solignac , N. Montblanc , T. Maroutian , A. Di Pietro , D. Ravelosona , G. Durin , L. Herrera Diez , G. Agnus

This study investigates how piezoelectric strain influences magnetic domain-wall (DW) motion in perpendicularly magnetized Ta/CoFeB/MgO ultrathin films grown on PMN-PT (011) substrates. Applying a gate voltage along the out-of-plane direction of the PMN-PT (011) substrate induces a non-volatile electrical polarization, producing a stable strain state (the poled state), which was confirmed using piezoresponse force microscopy. In this configuration, polar magneto-optical Kerr effect (P-MOKE) measurements reveal that this voltage-controlled remanent strain in the PMN-PT substrate can modulate DW dynamics and magnetic properties relative to the unpoled (as-grown) state. This response can be linked not only to a strain-controlled magnetic anisotropy but also to a strain-controlled change in the homogeneity of the magnetic landscape. The multiple polarization directions of the domains in the unpoled state of the PMN-PT can result in a wider anisotropy distribution in the magnetic system compared to the poled state. This can significantly affect DW nucleation/depinning fields, highlighting the role of piezoelectric strain in controlling DW dynamics. These results are of interest for the development of DW based magnetic memory applications with a reduced energy consumption.

本文研究了压电应变如何影响在PMN-PT（011）衬底上生长的垂直磁化Ta/CoFeB/MgO超薄膜的磁畴壁运动。在PMN-PT（011）衬底的面外方向施加栅极电压可诱导非易失性电极化，产生稳定的应变状态（极化状态），并通过压电响应力显微镜证实了这一点。在这种结构下，极性磁光克尔效应（P-MOKE）测量表明，PMN-PT衬底中的电压控制残余应变可以调制相对于未极化（生长）状态的DW动力学和磁性能。这种响应不仅与应变控制的磁各向异性有关，而且与应变控制的磁景观均匀性变化有关。PMN-PT在非极性状态下畴的多个极化方向导致磁系统的各向异性分布比极性状态更宽。这可以显著影响DW成核/脱屑场，突出了压电应变在控制DW动力学中的作用。这些结果对于开发基于DW的低能耗磁存储应用具有重要意义。

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引用次数: 0

Investigation of loss and noise in toroidal core current sensors 环形铁芯电流传感器损耗与噪声的研究

IF 3 3区材料科学 Q3 MATERIALS SCIENCE, MULTIDISCIPLINARY

Journal of Magnetism and Magnetic Materials

Pub Date : 2025-12-30 DOI: 10.1016/j.jmmm.2025.173788

Tingting Fan , Lizi Pan , Chenbo Zhao, Qingfang Liu, Jianbo Wang

Cobalt-based amorphous toroidal core are used to fabricate a giant magneto impedance current sensor in this work. By adjusting the bias current, a high sensitivity of 31.6 V/A is obtained, which can realize weak current detection. The core losses are then measured and calculated to analyze the noise level. The results shows that the core loss characteristics dominate the sensor's noise, besides that, the excitation current and DC bias current also affect the noise performance. Based on optimized parameters, a current threshold alarm is realized, achieving current threshold detection and alarm functionality. This study provides theoretical and experimental guidance for low-noise design optimization in current sensing.

本文采用钴基非晶环形磁芯制作巨磁阻电流传感器。通过调节偏置电流，获得31.6 V/ a的高灵敏度，可实现微弱电流检测。然后测量和计算磁芯损耗以分析噪声水平。结果表明，铁芯损耗特性是传感器噪声的主要影响因素，此外，励磁电流和直流偏置电流也影响传感器的噪声性能。根据优化后的参数，实现电流阈值告警，实现电流阈值检测和告警功能。该研究为电流传感的低噪声优化设计提供了理论和实验指导。

引用次数: 0

Inducing and/or redirecting magnetic anisotropy in Co films with collapsed hard-magnetization axes 硬磁化轴塌陷的Co薄膜中磁各向异性的诱导和/或重定向

IF 3 3区材料科学 Q3 MATERIALS SCIENCE, MULTIDISCIPLINARY

Journal of Magnetism and Magnetic Materials

Pub Date : 2025-12-30 DOI: 10.1016/j.jmmm.2025.173805

L.F.S. Azeredo , H.S. Acosta , A.M.H. de Andrade , J. Geshev

Magnetic anisotropy is a key characteristic of magnetic materials and is a prerequisite for magnetic hysteresis. In thin magnetic films, it is usually induced by applying magnetic field either during growth or in the course of a post-deposition treatment. This study presents a comparative study of different methods — in-field sputtering deposition, annealing and ion irradiation — for inducing uniaxial magnetic anisotropy and even changing its easy-magnetization direction in polycrystalline Co films presenting collapsed hard-magnetization axes. The latter stands for the presence of prominent peaks in the angular variations of the remanent magnetization and coercivity centered ninety degrees off of the easy axis. The advantages, disadvantages and limitations of the three different techniques used to induce magnetic anisotropy are evaluated and discussed.

磁各向异性是磁性材料的一个重要特性，也是磁滞的先决条件。在磁性薄膜中，它通常是在生长过程中或在沉积后处理过程中通过施加磁场引起的。本研究对比研究了在硬磁化轴坍塌的多晶Co薄膜中，采用场内溅射沉积、退火和离子辐照等不同方法诱导单轴磁各向异性，甚至改变其易磁化方向。后者表示在剩余磁化强度和矫顽力的角变化中存在显著的峰值，其中心距易轴90度。对三种不同磁各向异性诱导技术的优缺点和局限性进行了评价和讨论。

引用次数: 0