Pub Date : 2024-10-03DOI: 10.1016/j.jmmm.2024.172568
Somesh Chandra , Balmukund Shukla , V. Srihari , Rajkumar Gupta , Uday Deshpande , R. Venkatesh , Sujay Chakravarty , G.M. Bhalerao , R Govindaraj
The crystal structure of synthesized Mg0.946Cu2.054O3 compound was examined using Rietveld refinement of powder X-ray diffraction (XRD), revealing the presence of antisite defects in the form of substitution occupation of Mg atomic sites by Cu atoms upto ∼9 %. Detailed investigation by magnetic measurements around antiferromagnetic Néel transition around 95 K and below hints at the existence of paramagnetic component and short-range order due to presence of antisite defects, which is further supported by specific heat measurements.
通过对粉末 X 射线衍射 (XRD) 进行里特维尔德细化，对合成的 Mg0.946Cu2.054O3 化合物的晶体结构进行了研究，结果表明存在反斜长石缺陷，即镁原子位点被铜原子取代，取代率高达 9%。通过对 95 K 及以下反铁磁性奈尔转变附近的磁性测量进行详细研究，暗示由于存在反斜长石缺陷而存在顺磁成分和短程有序，比热测量进一步证实了这一点。
{"title":"Investigation of structural and magnetic properties of Mg0.946Cu2.054O3 compound","authors":"Somesh Chandra , Balmukund Shukla , V. Srihari , Rajkumar Gupta , Uday Deshpande , R. Venkatesh , Sujay Chakravarty , G.M. Bhalerao , R Govindaraj","doi":"10.1016/j.jmmm.2024.172568","DOIUrl":"10.1016/j.jmmm.2024.172568","url":null,"abstract":"<div><div>The crystal structure of synthesized Mg<sub>0.946</sub>Cu<sub>2.054</sub>O<sub>3</sub> compound was examined using Rietveld refinement of powder X-ray diffraction (XRD), revealing the presence of antisite defects in the form of substitution occupation of Mg atomic sites by Cu atoms upto ∼9 %. Detailed investigation by magnetic measurements around antiferromagnetic Néel transition around 95 K and below hints at the existence of paramagnetic component and short-range order due to presence of antisite defects, which is further supported by specific heat measurements.</div></div>","PeriodicalId":366,"journal":{"name":"Journal of Magnetism and Magnetic Materials","volume":"610 ","pages":"Article 172568"},"PeriodicalIF":2.5,"publicationDate":"2024-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142419002","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-10-03DOI: 10.1016/j.jmmm.2024.172557
Lei Jiang , Xiaolong Yang , Denghui Li , Guangyong Huang
Combined with two objectives of vibration reduction and energy harvesting, an integrated magnetorheological (MR) damper with energy harvesting and embedded channels is presented in this research. The effects of different structural parameters on the magnetic flux density and damping performance of the damping module are investigated using the finite element method. In addition, the effects of different frequencies, amplitudes, currents, and external resistances on the damping and energy harvesting characteristics of the proposed damper are experimentally studied. Simulation results demonstrate that the damping force first increases and then decreases with the increase of inner cylinder thickness and magnetic isolation height, increases with the increase of coil turns and current size, and decreases with the increase of outer cylinder thickness and magnetic isolation width. Simulation values of the damping force of the damping module are in good agreement with experimental data. Experimental results indicate that the damping force of the energy harvesting module drops as the external resistance rises. The output voltage of the energy harvesting module increases with the raise of external resistance. The average output power and the energy harvesting efficiency of the new damper reach 7.3 W and 53.5 % when A = 10 mm, f = 2 Hz, and R = 5 Ω.
结合减振和能量收集这两个目标，本研究提出了一种具有能量收集和嵌入式通道的集成磁流变（MR）阻尼器。采用有限元法研究了不同结构参数对磁通密度和阻尼模块阻尼性能的影响。此外，还通过实验研究了不同频率、振幅、电流和外部电阻对拟议阻尼器的阻尼和能量收集特性的影响。仿真结果表明，阻尼力随着内筒厚度和隔磁高度的增加先增大后减小，随着线圈匝数和电流大小的增加而增大，随着外筒厚度和隔磁宽度的增加而减小。阻尼模块阻尼力的模拟值与实验数据十分吻合。实验结果表明，能量收集模块的阻尼力随着外部电阻的增大而减小。能量收集模块的输出电压随着外部电阻的增大而增大。当 A = 10 mm、f = 2 Hz 和 R = 5 Ω 时，新型阻尼器的平均输出功率和能量收集效率分别达到 7.3 W 和 53.5 %。
{"title":"Simulation and characterization of an integrated MR damper with energy harvesting and embedded channels","authors":"Lei Jiang , Xiaolong Yang , Denghui Li , Guangyong Huang","doi":"10.1016/j.jmmm.2024.172557","DOIUrl":"10.1016/j.jmmm.2024.172557","url":null,"abstract":"<div><div>Combined with two objectives of vibration reduction and energy harvesting, an integrated magnetorheological (MR) damper with energy harvesting and embedded channels is presented in this research. The effects of different structural parameters on the magnetic flux density and damping performance of the damping module are investigated using the finite element method. In addition, the effects of different frequencies, amplitudes, currents, and external resistances on the damping and energy harvesting characteristics of the proposed damper are experimentally studied. Simulation results demonstrate that the damping force first increases and then decreases with the increase of inner cylinder thickness and magnetic isolation height, increases with the increase of coil turns and current size, and decreases with the increase of outer cylinder thickness and magnetic isolation width. Simulation values of the damping force of the damping module are in good agreement with experimental data. Experimental results indicate that the damping force of the energy harvesting module drops as the external resistance rises. The output voltage of the energy harvesting module increases with the raise of external resistance. The average output power and the energy harvesting efficiency of the new damper reach 7.3 W and 53.5 % when <em>A</em> = 10 mm, <em>f</em> = 2 Hz, and <em>R</em> = 5 Ω.</div></div>","PeriodicalId":366,"journal":{"name":"Journal of Magnetism and Magnetic Materials","volume":"610 ","pages":"Article 172557"},"PeriodicalIF":2.5,"publicationDate":"2024-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142419003","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-10-02DOI: 10.1016/j.jmmm.2024.172571
Asish K. Kundu , Md. Motin Seikh , Bernard Raveau
We have thoroughly studied the structure, magnetic and magneto-dielectric properties of Co4NbTaO9 along with the isotypic Co4Nb2O9, Co4Nb1.5Ta0.5O9 and Co3NiNb2O9 phases, which are noncollinear antiferromagnet with trigonal structure. The transition temperature decreases with Ta substitution, whereas it increases with Ni substitution. In the absence of external magnetic fields, no dielectric anomaly is noticed below the magnetic transition temperature. However, prominent dielectric peak appears under external magnetic fields and the peak magnitude increases with increasing field strengths, depicting magneto-dielectric and magnetoelectric phenomena. We describe the magnetic field induced dielectric effect due to the spin-flop magnetic transition.
我们深入研究了 Co4NbTaO9 以及同型 Co4Nb2O9、Co4Nb1.5Ta0.5O9 和 Co3NiNb2O9 相的结构、磁性和磁介电特性，它们都是具有三方结构的非共轭反铁磁体。过渡温度随 Ta 的取代而降低，随 Ni 的取代而升高。在没有外磁场的情况下，磁转变温度以下没有发现介电异常。然而，在外加磁场下会出现突出的介电峰值，且峰值大小随磁场强度的增加而增大，这描述了磁介电和磁电现象。我们描述了自旋翻转磁转变导致的磁场诱导介电效应。
{"title":"Magneto-dielectric effect in corundum-type oxide: Co4NbTaO9","authors":"Asish K. Kundu , Md. Motin Seikh , Bernard Raveau","doi":"10.1016/j.jmmm.2024.172571","DOIUrl":"10.1016/j.jmmm.2024.172571","url":null,"abstract":"<div><div>We have thoroughly studied the structure, magnetic and magneto-dielectric properties of Co<sub>4</sub>NbTaO<sub>9</sub> along with the isotypic Co<sub>4</sub>Nb<sub>2</sub>O<sub>9</sub>, Co<sub>4</sub>Nb<sub>1.5</sub>Ta<sub>0.5</sub>O<sub>9</sub> and Co<sub>3</sub>NiNb<sub>2</sub>O<sub>9</sub> phases, which are noncollinear antiferromagnet with trigonal structure. The transition temperature decreases with Ta substitution, whereas it increases with Ni substitution. In the absence of external magnetic fields, no dielectric anomaly is noticed below the magnetic transition temperature. However, prominent dielectric peak appears under external magnetic fields and the peak magnitude increases with increasing field strengths, depicting magneto-dielectric and magnetoelectric phenomena. We describe the magnetic field induced dielectric effect due to the spin-flop magnetic transition.</div></div>","PeriodicalId":366,"journal":{"name":"Journal of Magnetism and Magnetic Materials","volume":"610 ","pages":"Article 172571"},"PeriodicalIF":2.5,"publicationDate":"2024-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142419001","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-10-02DOI: 10.1016/j.jmmm.2024.172570
H. Gharsallah , M. Jeddi , M. Bejar , E. Dhahri , A. Koumina
In this research work, we investigated the correlation between the electrical and magnetic properties of the superparamagnetic compound La0.6Ca0.4MnO3 prepared by the citric-gel method. The confrontation of the experimental data with the theoretical models revealed that the conduction at low temperatures, in the ferromagnetic metallic phase, can be mainly described by electron–electron and electron-magnon interactions. The contribution of the interaction, became weak for strong magnetic fields. At high temperatures, in the paramagnetic semiconductor phase, the thermally activated hopping model proved to be the most appropriate to fit the experimental data. To describe the resistivity behavior in a wide temperature range including the phase transition region between the and phases, we adopted the percolation model, based on the phase segregation mechanism.
{"title":"Correlation between magnetic and electrical properties of the superparamagnetic La0.6Ca0.4MnO3 compound","authors":"H. Gharsallah , M. Jeddi , M. Bejar , E. Dhahri , A. Koumina","doi":"10.1016/j.jmmm.2024.172570","DOIUrl":"10.1016/j.jmmm.2024.172570","url":null,"abstract":"<div><div>In this research work, we investigated the correlation between the electrical and magnetic properties of the superparamagnetic compound La<sub>0.6</sub>Ca<sub>0.4</sub>MnO<sub>3</sub> <span><math><mrow><mo>(</mo><mi>S</mi><mn>0</mn><mi>C</mi><mn>1</mn><mo>)</mo></mrow></math></span> prepared by the citric-gel method. The confrontation of the experimental data with the theoretical models revealed that the conduction at low temperatures, in the ferromagnetic metallic <span><math><mrow><mo>(</mo><mi>F</mi><mi>M</mi><mi>M</mi><mo>)</mo></mrow></math></span> phase, can be mainly described by electron–electron <span><math><mrow><mo>(</mo><mi>e</mi><mo>-</mo><mi>e</mi><mo>)</mo></mrow></math></span> and electron-magnon <span><math><mrow><mo>(</mo><mi>e</mi><mo>-</mo><mi>m</mi><mo>)</mo></mrow></math></span> interactions. The contribution of the <span><math><mrow><mo>(</mo><mi>e</mi><mo>-</mo><mi>m</mi><mo>)</mo></mrow></math></span> interaction, became weak for strong magnetic fields. At high temperatures, in the paramagnetic semiconductor <span><math><mrow><mo>(</mo><mi>P</mi><mi>M</mi><mi>S</mi><mi>C</mi><mo>)</mo></mrow></math></span> phase, the thermally activated hopping <span><math><mrow><mo>(</mo><mi>T</mi><mi>A</mi><mi>H</mi><mo>)</mo></mrow></math></span> model proved to be the most appropriate to fit the experimental data. To describe the resistivity behavior in a wide temperature range including the phase transition region between the <span><math><mrow><mo>(</mo><mi>F</mi><mi>M</mi><mi>M</mi><mo>)</mo></mrow></math></span> and <span><math><mrow><mo>(</mo><mi>P</mi><mi>M</mi><mi>S</mi><mi>C</mi><mo>)</mo></mrow></math></span> phases, we adopted the percolation model, based on the phase segregation mechanism.</div></div>","PeriodicalId":366,"journal":{"name":"Journal of Magnetism and Magnetic Materials","volume":"610 ","pages":"Article 172570"},"PeriodicalIF":2.5,"publicationDate":"2024-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142418997","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-10-02DOI: 10.1016/j.jmmm.2024.172562
Khalid Ibne Masood, Raviv Raich, Albrecht Jander, Pallavi Dhagat
To infer anisotropy parameters of magnetic materials from experimental measurements of ferromagnetic resonance (FMR) (with data comprising resonant frequencies and corresponding resonant magnetic fields), a fitting procedure to the theoretical model is essential. The governing equation for this fitting process is the Smit–Beljers equation (SB equation), which links FMR frequencies to resonant magnetic field values and anisotropy parameters nonlinearly, and through the equilibrium magnetization angle values, which also depend on the same anisotropy parameters and magnetic field values. Obtaining an analytical expression for this equation is rarely possible. In this paper, we address the challenges posed by the Smit–Beljers equation and propose a two-step self-consistent algorithm to extract the relevant parameters efficiently.
{"title":"A two-step self consistent algorithm for extracting magnetic anisotropy constants from angle-dependent ferromagnetic resonance measurements","authors":"Khalid Ibne Masood, Raviv Raich, Albrecht Jander, Pallavi Dhagat","doi":"10.1016/j.jmmm.2024.172562","DOIUrl":"10.1016/j.jmmm.2024.172562","url":null,"abstract":"<div><div>To infer anisotropy parameters of magnetic materials from experimental measurements of ferromagnetic resonance (FMR) (with data comprising resonant frequencies and corresponding resonant magnetic fields), a fitting procedure to the theoretical model is essential. The governing equation for this fitting process is the Smit–Beljers equation (SB equation), which links FMR frequencies to resonant magnetic field values and anisotropy parameters nonlinearly, and through the equilibrium magnetization angle values, which also depend on the same anisotropy parameters and magnetic field values. Obtaining an analytical expression for this equation is rarely possible. In this paper, we address the challenges posed by the Smit–Beljers equation and propose a two-step self-consistent algorithm to extract the relevant parameters efficiently.</div></div>","PeriodicalId":366,"journal":{"name":"Journal of Magnetism and Magnetic Materials","volume":"610 ","pages":"Article 172562"},"PeriodicalIF":2.5,"publicationDate":"2024-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142433128","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-10-02DOI: 10.1016/j.jmmm.2024.172572
Zeinab Harajli, Samih Isber, Mohammad Haidar
Here, we study the influence of magnetic properties on the spin-pumping effect of the Yttrium Iron Garnet/Platinum (YIG/Pt) bilayer. YIG films were deposited by pulsed laser deposition under variable oxygen pressures. Using broadband ferromagnetic resonance techniques, the magnetic properties of the YIG films were measured. We analyzed the spin-pumping effect in these films by measuring damping changes in samples with and without Pt layers, enabling the calculation of spin-mixing conductance. Experimental results show that films prepared at high oxygen pressure exhibit lower magnetization and reduced spin pumping, , leading to a decreased spin mixing conductance, . We report a variation in ranging from to . These findings underscore the sensitivity of spin transport properties to deposition parameters in YIG-based spintronic devices.
{"title":"Optimizing spin pumping in Yttrium Iron Garnet/Platinum bilayers under varying oxygen pressure","authors":"Zeinab Harajli, Samih Isber, Mohammad Haidar","doi":"10.1016/j.jmmm.2024.172572","DOIUrl":"10.1016/j.jmmm.2024.172572","url":null,"abstract":"<div><div>Here, we study the influence of magnetic properties on the spin-pumping effect of the Yttrium Iron Garnet/Platinum (YIG/Pt) bilayer. YIG films were deposited by pulsed laser deposition under variable oxygen pressures. Using broadband ferromagnetic resonance techniques, the magnetic properties of the YIG films were measured. We analyzed the spin-pumping effect in these films by measuring damping changes in samples with and without Pt layers, enabling the calculation of spin-mixing conductance. Experimental results show that films prepared at high oxygen pressure exhibit lower magnetization and reduced spin pumping, <span><math><msub><mrow><mi>α</mi></mrow><mrow><mi>s</mi><mi>p</mi></mrow></msub></math></span>, leading to a decreased spin mixing conductance, <span><math><msup><mrow><mi>g</mi></mrow><mrow><mi>↑</mi><mi>↓</mi></mrow></msup></math></span>. We report a variation in <span><math><msup><mrow><mi>g</mi></mrow><mrow><mi>↑</mi><mi>↓</mi></mrow></msup></math></span> ranging from <span><math><mrow><mn>4</mn><mo>.</mo><mn>2</mn><mo>×</mo><mn>1</mn><msup><mrow><mn>0</mn></mrow><mrow><mn>18</mn></mrow></msup></mrow></math></span> to <span><math><mrow><mn>15</mn><mo>.</mo><mn>6</mn><mo>×</mo><mn>1</mn><msup><mrow><mn>0</mn></mrow><mrow><mn>18</mn></mrow></msup><mo>,</mo><msup><mrow><mtext>m</mtext></mrow><mrow><mo>−</mo><mn>2</mn></mrow></msup></mrow></math></span>. These findings underscore the sensitivity of spin transport properties to deposition parameters in YIG-based spintronic devices.</div></div>","PeriodicalId":366,"journal":{"name":"Journal of Magnetism and Magnetic Materials","volume":"610 ","pages":"Article 172572"},"PeriodicalIF":2.5,"publicationDate":"2024-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142419004","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-10-01DOI: 10.1016/j.jmmm.2024.172563
A. Nfissi , R. El Fdil , A. Samih , D. Kabouchi , Z. Fadil , Chaitany Jayprakash Raorane , Ahmad A. Ifseisi , Mohamed E. Assal , E. Salmani
This study utilizes first-principles calculations to investigate the magnetic properties of NiO doped and co-doped with transition metals (TM) such as vanadium (V), chromium (Cr), and manganese (Mn) at low concentrations. By employing local density approximation (LDA) and self-interaction corrected local density approximation (LDA-SIC), we uncover a pronounced half-metallic behavior in the modified NiO systems. Additionally, the introduction of nitrogen into the doped NiO results in a substantial shift in the density of states (DOS), transforming the material from a non-half-metallic to a distinctly half-metallic ferromagnetic state. These findings offer valuable insights into the potential of doped and co-doped NiO for advancing spintronic applications.
{"title":"Exploring Half-Metallicity in NiO via TM and NTM Doping: Insights from LDA and LDA-SIC approaches","authors":"A. Nfissi , R. El Fdil , A. Samih , D. Kabouchi , Z. Fadil , Chaitany Jayprakash Raorane , Ahmad A. Ifseisi , Mohamed E. Assal , E. Salmani","doi":"10.1016/j.jmmm.2024.172563","DOIUrl":"10.1016/j.jmmm.2024.172563","url":null,"abstract":"<div><div>This study utilizes first-principles calculations to investigate the magnetic properties of NiO doped and co-doped with transition metals (TM) such as vanadium (V), chromium (Cr), and manganese (Mn) at low concentrations. By employing local density approximation (LDA) and self-interaction corrected local density approximation (LDA-SIC), we uncover a pronounced half-metallic behavior in the modified NiO systems. Additionally, the introduction of nitrogen into the doped NiO results in a substantial shift in the density of states (DOS), transforming the material from a non-half-metallic to a distinctly half-metallic ferromagnetic state. These findings offer valuable insights into the potential of doped and co-doped NiO for advancing spintronic applications.</div></div>","PeriodicalId":366,"journal":{"name":"Journal of Magnetism and Magnetic Materials","volume":"610 ","pages":"Article 172563"},"PeriodicalIF":2.5,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142418994","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Recent research interest has surged in magnetic composite materials, driven by the increasing demand for permanent magnets, magnetic fluids, and magnetic sensors, in various technological applications. Among all these materials, the 1BaFe12O19 + (x) CuFe2O4 composites have developed as particularly promising in terms of its magnetic properties. However, despite its potential, detailed insights into the magnetic characteristics of this composite remain scarce in the existing literature. In this article, we address this gap by thoroughly investigating the magnetic properties of the 1BaFe12O19 + (x) CuFe2O4 composite across a range of compositions (x = 1 to 6). This present study focused on both low and high applied magnetic fields, examining the material’s behavior in Rayleigh region as well as under intense magnetic influences. At low magnetic fields, the M−H loop exhibits distinctive elliptical or lens shape. Notably, the susceptibility (χm) initially increases but then declines after reaching a critical threshold with increasing magnetic field strength. The analysis of different magnetic parameters, including maximum magnetization (Mm), remanent magnetization (Mr), coercive field (Hc), and the ratio of remanent to maximum magnetization (Mr/Mm), derived from the M−H loops across different applied magnetic fields have been reported here. According to present research, these magnetic parameters show a growing trendency with increasing applied magnetic field strength until they get close to saturation. Results are correlated with the magnetic domain wall dynamics.
{"title":"Exploration of Rayleigh loop vis-to-vis high applied magnetic field hysteresis loops phenomena in barium hexaferrite-Copper ferrite ferrimagnetic composites","authors":"Murli Kumar Manglam , Sushree Nibedita Rout , Mukesh Kumar Yadav , Lagen Kumar Pradhan , Lawrence Kumar , Manoranjan Kar","doi":"10.1016/j.jmmm.2024.172569","DOIUrl":"10.1016/j.jmmm.2024.172569","url":null,"abstract":"<div><div>Recent research interest has surged in magnetic composite materials, driven by the increasing demand for permanent magnets, magnetic fluids, and magnetic sensors, in various technological applications. Among all these materials, the 1BaFe<sub>12</sub>O<sub>19</sub> + (x) CuFe<sub>2</sub>O<sub>4</sub> composites have developed as particularly promising in terms of its magnetic properties. However, despite its potential, detailed insights into the magnetic characteristics of this composite remain scarce in the existing literature. In this article, we address this gap by thoroughly investigating the magnetic properties of the 1BaFe<sub>12</sub>O<sub>19</sub> + (x) CuFe<sub>2</sub>O<sub>4</sub> composite across a range of compositions (x = 1 to 6). This present study focused on both low and high applied magnetic fields, examining the material’s behavior in Rayleigh region as well as under intense magnetic influences. At low magnetic fields, the <em>M−H</em> loop exhibits distinctive elliptical or lens shape. Notably, the susceptibility (<em>χ<sub>m</sub></em>) initially increases but then declines after reaching a critical threshold with increasing magnetic field strength. The analysis of different magnetic parameters, including maximum magnetization (<em>M<sub>m</sub></em>), remanent magnetization (<em>M<sub>r</sub></em>), coercive field (<em>H<sub>c</sub></em>), and the ratio of remanent to maximum magnetization (<em>M<sub>r</sub>/M<sub>m</sub></em>), derived from the <em>M−H</em> loops across different applied magnetic fields have been reported here. According to present research, these magnetic parameters show a growing trendency with increasing applied magnetic field strength until they get close to saturation. Results are correlated with the magnetic domain wall dynamics.</div></div>","PeriodicalId":366,"journal":{"name":"Journal of Magnetism and Magnetic Materials","volume":"610 ","pages":"Article 172569"},"PeriodicalIF":2.5,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142418894","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-10-01DOI: 10.1016/j.jmmm.2024.172561
Hui Liu , Mengwu Huo , Chaoxin Huang , Xing Huang , Hualei Sun , Lan Chen , Juping Xu , Wen Yin , Runxia Li , Meng Wang
We report experimental studies on a series of Rb(CoNi)2Se2 (0.02 0.9) powder and single crystal samples using x-ray diffraction, neutron diffraction, magnetic susceptibility, and electronic transport measurements. All compositions are metallic and adopt the body-centered tetragonal structure with space group. Anisotropic magnetic susceptibilities measured on single crystal samples suggest that Rb(CoNi)2Se2 undergo an evolution from ferromagnetism to antiferromagnetism, and finally to paramagnetism with increasing Ni concentration. Neutron diffraction measurements on the samples with = 0.1, 0.4, and 0.6 reveal an -type antiferromagnetic order with moments lying in the plane. The moment size changes from 0.69 () to 2.80 () per Co ions. Our results demonstrate that dilution of the magnetic Co ions by substitution of nonmagnetic Ni ions induces magnetic localization and evolution from itinerant to localized magnetism in Rb(CoNi)2Se2.
我们报告了利用 X 射线衍射、中子衍射、磁感应强度和电子传输测量对一系列 Rb(Co1-xNix)2Se2 (0.02 ≤x≤ 0.9) 粉末和单晶样品进行的实验研究。所有成分均为金属，并采用 I4/mmm 空间群的体心四方结构。在单晶样品上测量到的各向异性磁感应强度表明，随着镍浓度的增加，Rb(Co1-xNix)2Se2 经历了从铁磁性到反铁磁性，最后到顺磁性的演变过程。对 x = 0.1、0.4 和 0.6 的样品进行的中子衍射测量显示了矩位于 ab 平面的 A 型反铁磁阶。每 Co 离子的力矩大小从 0.69（x=0.1）变为 2.80μB（x=0.6）。我们的研究结果表明，通过非磁性镍离子的替代稀释了磁性钴离子，从而诱导了 Rb(Co1-xNix)2Se2 的磁性局部化以及从巡回磁性到局部磁性的演变。
{"title":"Dilution induced magnetic localization in Rb(Co1−xNix)2Se2 single crystals","authors":"Hui Liu , Mengwu Huo , Chaoxin Huang , Xing Huang , Hualei Sun , Lan Chen , Juping Xu , Wen Yin , Runxia Li , Meng Wang","doi":"10.1016/j.jmmm.2024.172561","DOIUrl":"10.1016/j.jmmm.2024.172561","url":null,"abstract":"<div><div>We report experimental studies on a series of Rb(Co<span><math><msub><mrow></mrow><mrow><mn>1</mn><mo>−</mo><mi>x</mi></mrow></msub></math></span>Ni<span><math><msub><mrow></mrow><mrow><mi>x</mi></mrow></msub></math></span>)<sub>2</sub>Se<sub>2</sub> (0.02 <span><math><mrow><mo>≤</mo><mi>x</mi><mo>≤</mo></mrow></math></span> 0.9) powder and single crystal samples using x-ray diffraction, neutron diffraction, magnetic susceptibility, and electronic transport measurements. All compositions are metallic and adopt the body-centered tetragonal structure with <span><math><mrow><mi>I</mi><mn>4</mn><mo>/</mo><mi>m</mi><mi>m</mi><mi>m</mi></mrow></math></span> space group. Anisotropic magnetic susceptibilities measured on single crystal samples suggest that Rb(Co<span><math><msub><mrow></mrow><mrow><mn>1</mn><mo>−</mo><mi>x</mi></mrow></msub></math></span>Ni<span><math><msub><mrow></mrow><mrow><mi>x</mi></mrow></msub></math></span>)<sub>2</sub>Se<sub>2</sub> undergo an evolution from ferromagnetism to antiferromagnetism, and finally to paramagnetism with increasing Ni concentration. Neutron diffraction measurements on the samples with <span><math><mi>x</mi></math></span> = 0.1, 0.4, and 0.6 reveal an <span><math><mi>A</mi></math></span>-type antiferromagnetic order with moments lying in the <span><math><mrow><mi>a</mi><mi>b</mi></mrow></math></span> plane. The moment size changes from 0.69 (<span><math><mrow><mi>x</mi><mo>=</mo><mn>0</mn><mo>.</mo><mn>1</mn></mrow></math></span>) to 2.80<span><math><msub><mrow><mi>μ</mi></mrow><mrow><mi>B</mi></mrow></msub></math></span> (<span><math><mrow><mi>x</mi><mo>=</mo><mn>0</mn><mo>.</mo><mn>6</mn></mrow></math></span>) per Co ions. Our results demonstrate that dilution of the magnetic Co ions by substitution of nonmagnetic Ni ions induces magnetic localization and evolution from itinerant to localized magnetism in Rb(Co<span><math><msub><mrow></mrow><mrow><mn>1</mn><mo>−</mo><mi>x</mi></mrow></msub></math></span>Ni<span><math><msub><mrow></mrow><mrow><mi>x</mi></mrow></msub></math></span>)<sub>2</sub>Se<sub>2</sub>.</div></div>","PeriodicalId":366,"journal":{"name":"Journal of Magnetism and Magnetic Materials","volume":"610 ","pages":"Article 172561"},"PeriodicalIF":2.5,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142418998","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-10-01DOI: 10.1016/j.jmmm.2024.172565
Marek Przybylski
Power losses from motors and drives can decrease their efficiency. The development of devices with high efficiency is a necessity nowadays, with a view to reducing CO2 emissions. The application of new magnetic materials is one method for increasing the efficiency of motors, although prediction and calculation of the losses in the magnetic circuits of motors are also very important. To reduce the iron losses, iron powder composites are used here instead of Fe-Si laminated steel sheets, in a low-power switched reluctance motor (SRM), and a new method of determining the iron loss in the magnetic circuit is developed. Through the use of new materials in the motor, we can achieve a 19% decrease in the iron loss in comparison to a commercial motor. A comparison of the measurement results for our new method of iron loss prediction showed that the difference is approximately 20-26%, depending on the type of magnetic circuit used for the motor. The usage of soft magnetic composites rather than electrical steel sheets can decrease the loss in magnetic circuits. The results from our new method of determination of iron loss are in good agreement with results of measurements, meaning that it can be applied in a detailed analysis of SRMs. The application of soft magnetic composites in electromagnetic and electromechanical converters is a new method for lowering iron losses in new devices. The determination of such losses in SRMs is still challenging, and the proposed method broadens the state of the art in this area. The method developed here is based on motor current measurements, FEM calculations, and measurements of the magnetisation curves and iron loss for samples according to IEC standards. The results obtained in this work can be used by designers for the development of new kinds of SRMs.
{"title":"New method for determining iron power losses in switched reluctance motors with laminated and composite magnetic cores","authors":"Marek Przybylski","doi":"10.1016/j.jmmm.2024.172565","DOIUrl":"10.1016/j.jmmm.2024.172565","url":null,"abstract":"<div><div>Power losses from motors and drives can decrease their efficiency. The development of devices with high efficiency is a necessity nowadays, with a view to reducing CO<sub>2</sub> emissions. The application of new magnetic materials is one method for increasing the efficiency of motors, although prediction and calculation of the losses in the magnetic circuits of motors are also very important. To reduce the iron losses, iron powder composites are used here instead of Fe-Si laminated steel sheets, in a low-power switched reluctance motor (SRM), and a new method of determining the iron loss in the magnetic circuit is developed. Through the use of new materials in the motor, we can achieve a 19% decrease in the iron loss in comparison to a commercial motor. A comparison of the measurement results for our new method of iron loss prediction showed that the difference is approximately 20-26%, depending on the type of magnetic circuit used for the motor. The usage of soft magnetic composites rather than electrical steel sheets can decrease the loss in magnetic circuits. The results from our new method of determination of iron loss are in good agreement with results of measurements, meaning that it can be applied in a detailed analysis of SRMs. The application of soft magnetic composites in electromagnetic and electromechanical converters is a new method for lowering iron losses in new devices. The determination of such losses in SRMs is still challenging, and the proposed method broadens the state of the art in this area. The method developed here is based on motor current measurements, FEM calculations, and measurements of the magnetisation curves and iron loss for samples according to IEC standards. The results obtained in this work can be used by designers for the development of new kinds of SRMs.</div></div>","PeriodicalId":366,"journal":{"name":"Journal of Magnetism and Magnetic Materials","volume":"610 ","pages":"Article 172565"},"PeriodicalIF":2.5,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142440892","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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