Journal of Magnetism and Magnetic Materials最新文献

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Anomalous switching pattern in the ferrimagnetic memory cell 铁磁记忆单元中的异常开关模式
IF 2.5 3区 材料科学
Journal of Magnetism and Magnetic Materials Pub Date : 2024-11-02 DOI: 10.1016/j.jmmm.2024.172614
Zhuo Xu , Zhengping Yuan , Xue Zhang , Zhengde Xu , Yixiao Qiao , Yumeng Yang , Zhifeng Zhu
{"title":"Anomalous switching pattern in the ferrimagnetic memory cell","authors":"Zhuo Xu ,&nbsp;Zhengping Yuan ,&nbsp;Xue Zhang ,&nbsp;Zhengde Xu ,&nbsp;Yixiao Qiao ,&nbsp;Yumeng Yang ,&nbsp;Zhifeng Zhu","doi":"10.1016/j.jmmm.2024.172614","DOIUrl":"10.1016/j.jmmm.2024.172614","url":null,"abstract":"<div><div>Replacing the ferromagnet with ferrimagnet (FiM) in the magnetic tunnel junction (MTJ) allows faster magnetization switching in picoseconds. The operation of a memory cell that consists of the MTJ and a transistor requires reversable magnetization switching. When a constant voltage is applied, we find that the spin-transfer torque can only switch the FiM-MTJ from parallel to antiparallel state. This stems from the small switching window of FiM and the dynamic resistance variation during the magnetization switching. We find the resulting current variation can be suppressed by reducing the magnetoresistance ratio. Furthermore, we demonstrate that the switching window can be expanded by adjusting the amount of Gd in FiM. We predict that the polarity of both switching current (<em>J</em><sub>c,switch</sub>) and oscillation current (<em>J</em><sub>c,osc</sub>) reverses at the angular momentum compensation point but not the magnetization compensation point. This anomalous dynamic behavior is attributed to the different physical nature of magnetization switching and oscillation in FiM, which must be considered when designing FiM-based MRAM.</div></div>","PeriodicalId":366,"journal":{"name":"Journal of Magnetism and Magnetic Materials","volume":"611 ","pages":"Article 172614"},"PeriodicalIF":2.5,"publicationDate":"2024-11-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142652560","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}
引用次数: 0
Magnetic field effects on the thermal performance of Fe3O4 nanofluids in a forced convection system 磁场对强制对流系统中 Fe3O4 纳米流体热性能的影响
IF 2.5 3区 材料科学
Journal of Magnetism and Magnetic Materials Pub Date : 2024-11-02 DOI: 10.1016/j.jmmm.2024.172637
Mohammadmahdi Kamyabi, Seyed Mohammad Sadegh Hosseini
{"title":"Magnetic field effects on the thermal performance of Fe3O4 nanofluids in a forced convection system","authors":"Mohammadmahdi Kamyabi,&nbsp;Seyed Mohammad Sadegh Hosseini","doi":"10.1016/j.jmmm.2024.172637","DOIUrl":"10.1016/j.jmmm.2024.172637","url":null,"abstract":"<div><div>This study experimentally investigates the effects of magnetic field strength, Reynolds number, and nanoparticle concentration on the unsteady heat transfer characteristics of a Fe<sub>3</sub>O<sub>4</sub>-water nanofluid. The nanofluid was prepared by dispersing nanoparticles in water at concentrations of 0 %, 0.08% v/v and 0.16% v/v, using a stabilizer to maintain dispersion. A double-pipe system, encased in a copper coil (solenoid), was employed to facilitate heat exchange between tap water and the nanofluid under magnetic field. The solenoid exerts the desired magnetic field. The Taguchi method was utilized for experimental design and analysis. Results indicate that the Reynolds number, magnetic field strength, and nanofluid concentration all enhance the heat transfer rate; however, their effects differ due to distinct mechanisms of action. Analysis of variance reveals that the Reynolds number has the most significant impact although at low Reynolds only. This is while the effects of nanoparticle concentration and magnetic field strength are comparable. The findings suggest that even a magnetic field aligned with the fluid flow can serve as an auxiliary factor to enhance heat transfer in ferrofluids, particularly when increasing nanoparticle concentration is constrained by rising pressure drops and the risk of agglomeration.</div></div>","PeriodicalId":366,"journal":{"name":"Journal of Magnetism and Magnetic Materials","volume":"611 ","pages":"Article 172637"},"PeriodicalIF":2.5,"publicationDate":"2024-11-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142652558","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}
引用次数: 0
Effective spin filter and diode based on triple magnetic junction 基于三磁结的有效自旋滤波器和二极管
IF 2.5 3区 材料科学
Journal of Magnetism and Magnetic Materials Pub Date : 2024-11-01 DOI: 10.1016/j.jmmm.2024.172635
M. Wilczyński, K. Zberecki, M. Wierzbicki
{"title":"Effective spin filter and diode based on triple magnetic junction","authors":"M. Wilczyński,&nbsp;K. Zberecki,&nbsp;M. Wierzbicki","doi":"10.1016/j.jmmm.2024.172635","DOIUrl":"10.1016/j.jmmm.2024.172635","url":null,"abstract":"<div><div>The charge current flowing through the triple junction composed of ferromagnetic external electrodes and inner layers of different thickness separated by three non-magnetic barriers is analysed in four colinear magnetic configurations. The thickness of the inner layers and the bias voltage can be set in such a way that the junction can act as a tunnel diode with current flowing effectively in one specific direction. The diode properties of the junction can be adjusted by a change of relative orientation of magnetic moments in the inner layers and electrodes; especially the junction can act as a diode in only one magnetic configuration. Magnetic configuration switching can also reverse the direction of the flow of tunnel current.</div></div>","PeriodicalId":366,"journal":{"name":"Journal of Magnetism and Magnetic Materials","volume":"611 ","pages":"Article 172635"},"PeriodicalIF":2.5,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142578595","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}
引用次数: 0
Enhanced low field magnetocaloric effect through Fe doping induced ferromagnetic transition in HoCo0.8Fe0.2C compound 通过在 HoCo0.8Fe0.2C 化合物中掺铁诱导铁磁转变增强低磁场磁致效应
IF 2.5 3区 材料科学
Journal of Magnetism and Magnetic Materials Pub Date : 2024-11-01 DOI: 10.1016/j.jmmm.2024.172632
Zhihong Hao , Xiaojuan Wang , Yao Liu , Taosheng Zhong , Lina Zhang , Changwang Yuan , Licheng Xiao , Hui Liu , Juguo Zhang
{"title":"Enhanced low field magnetocaloric effect through Fe doping induced ferromagnetic transition in HoCo0.8Fe0.2C compound","authors":"Zhihong Hao ,&nbsp;Xiaojuan Wang ,&nbsp;Yao Liu ,&nbsp;Taosheng Zhong ,&nbsp;Lina Zhang ,&nbsp;Changwang Yuan ,&nbsp;Licheng Xiao ,&nbsp;Hui Liu ,&nbsp;Juguo Zhang","doi":"10.1016/j.jmmm.2024.172632","DOIUrl":"10.1016/j.jmmm.2024.172632","url":null,"abstract":"<div><div>The development of high-performance magnetocaloric materials has garnered significant attention due to their potential applications in magnetic refrigeration technology. Element doping has emerged as a crucial strategy for enhancing the magnetocaloric properties of these materials. In this study, we present the enhanced magnetocaloric effect in the HoCo<sub>0.8</sub>Fe<sub>0.2</sub>C compound through Fe doping. The Fe doping not only induces a ferromagnetic transition but also significantly improves the magnetocaloric performance of the compound. Under a magnetic field change from 0 to 7 T, the HoCo<sub>0.8</sub>Fe<sub>0.2</sub>C compound exhibits a maximum magnetic entropy change (<span><math><msubsup><mrow><mo>-</mo><mi>Δ</mi><mi>S</mi></mrow><mrow><mi>M</mi></mrow><mrow><mi>max</mi></mrow></msubsup></math></span>) of 20.5 J/kg K and a refrigerant capacity (RC) of 573.3 J/kg. Additionally, this compound undergoes a spin reorientation transition at 11 K and a ferromagnetic to paramagnetic transition at 18 K. These transitions are critical to understanding the magnetocaloric behavior of the material. The results highlight the potential of Fe-doped HoCo<sub>0.8</sub>Fe<sub>0.2</sub>C as an efficient magnetocaloric material, contributing to the advancement of magnetic refrigeration technology at low temperatures. Our study underscores the impact of element doping on the magnetic and magnetocaloric properties of intermetallic compounds.</div></div>","PeriodicalId":366,"journal":{"name":"Journal of Magnetism and Magnetic Materials","volume":"611 ","pages":"Article 172632"},"PeriodicalIF":2.5,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142587241","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}
引用次数: 0
Magnetic susceptibility and heat capacity of a quasi-spin chain compound, Li2CuO2 准自旋链化合物 Li2CuO2 的磁感应强度和热容量
IF 2.5 3区 材料科学
Journal of Magnetism and Magnetic Materials Pub Date : 2024-11-01 DOI: 10.1016/j.jmmm.2024.172617
Ashiwini Balodhi, Min Gyu Kim
{"title":"Magnetic susceptibility and heat capacity of a quasi-spin chain compound, Li2CuO2","authors":"Ashiwini Balodhi,&nbsp;Min Gyu Kim","doi":"10.1016/j.jmmm.2024.172617","DOIUrl":"10.1016/j.jmmm.2024.172617","url":null,"abstract":"<div><div>Magnetization and heat capacity (<span><math><msub><mrow><mi>C</mi></mrow><mrow><mi>p</mi></mrow></msub></math></span>) measurements were performed on blade-shaped single crystals of Li<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span>CuO<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span>, a one-dimensional spin-chain compound synthesized via the flux method. The magnetization and heat capacity measurements confirm a long-range antiferromagnetic transition at <span><math><msub><mrow><mi>T</mi></mrow><mrow><mi>N</mi></mrow></msub></math></span> = 9.3 K. The magnetic susceptibility, <span><math><mi>χ</mi></math></span> with magnetic field applied parallel (<span><math><msub><mrow><mi>χ</mi></mrow><mrow><mo>∥</mo><mi>b</mi></mrow></msub></math></span>) and perpendicular (<span><math><msub><mrow><mi>χ</mi></mrow><mrow><mo>⊥</mo><mi>b</mi></mrow></msub></math></span>) to the spin chain direction (crystallographic <span><math><mi>b</mi></math></span>-axis) is reported. <span><math><mrow><mi>χ</mi><mrow><mo>(</mo><mi>T</mi><mo>)</mo></mrow></mrow></math></span> measurements reveal anisotropic behavior, with <span><math><msub><mrow><mi>χ</mi></mrow><mrow><mo>⊥</mo><mi>b</mi></mrow></msub></math></span> <span><math><mrow><mo>&gt;</mo><msub><mrow><mi>χ</mi></mrow><mrow><mo>∥</mo><mi>b</mi></mrow></msub></mrow></math></span> in the temperature range <span><math><mrow><msub><mrow><mi>T</mi></mrow><mrow><mi>N</mi></mrow></msub><mo>&lt;</mo><mi>T</mi><mo>&lt;</mo><mn>350</mn></mrow></math></span> K, with a ratio of <span><math><mrow><msub><mrow><mi>χ</mi></mrow><mrow><mo>⊥</mo></mrow></msub><mo>/</mo><msub><mrow><mi>χ</mi></mrow><mrow><mo>∥</mo></mrow></msub></mrow></math></span> = 1.15 at 300 K and with <span><math><msub><mrow><mi>χ</mi></mrow><mrow><mo>⊥</mo><mi>b</mi></mrow></msub></math></span> <span><math><mrow><mo>&lt;</mo><msub><mrow><mi>χ</mi></mrow><mrow><mo>∥</mo><mi>b</mi></mrow></msub></mrow></math></span> at <span><math><mrow><mi>T</mi><mo>=</mo><mn>2</mn></mrow></math></span> K, with a ratio of <span><math><mrow><msub><mrow><mi>χ</mi></mrow><mrow><mo>⊥</mo></mrow></msub><mo>/</mo><msub><mrow><mi>χ</mi></mrow><mrow><mo>∥</mo></mrow></msub></mrow></math></span> = 0.86 at 2 K. Unlike the previous studies reporting ferromagnetic components at low temperatures, we report the absence of a ferromagnetic ordering at low temperatures.</div></div>","PeriodicalId":366,"journal":{"name":"Journal of Magnetism and Magnetic Materials","volume":"611 ","pages":"Article 172617"},"PeriodicalIF":2.5,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142587242","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}
引用次数: 0
Structural, magnetic, elastic, and thermoelectric properties of Ba2InOsO6 double perovskite in the cubic phase: A DFT + U study with spin-orbit-coupling 立方相 Ba2InOsO6 双包晶的结构、磁性、弹性和热电特性:利用自旋轨道耦合的 DFT + U 研究
IF 2.5 3区 材料科学
Journal of Magnetism and Magnetic Materials Pub Date : 2024-10-29 DOI: 10.1016/j.jmmm.2024.172629
Lakhdar Benahmedi, Anissa Besbes, Radouan Djelti
{"title":"Structural, magnetic, elastic, and thermoelectric properties of Ba2InOsO6 double perovskite in the cubic phase: A DFT + U study with spin-orbit-coupling","authors":"Lakhdar Benahmedi,&nbsp;Anissa Besbes,&nbsp;Radouan Djelti","doi":"10.1016/j.jmmm.2024.172629","DOIUrl":"10.1016/j.jmmm.2024.172629","url":null,"abstract":"<div><div>In this study, we comprehensively investigate the structural, electronic, magnetic, elastic, and thermal properties of the double perovskite Ba<sub>2</sub>InOsO<sub>6</sub> using density functional theory (DFT). Our results show that the ferromagnetic phase is the most stable, with the net magnetic moment primarily arising from the Os atom. The half-metallic behavior exhibited by Ba<sub>2</sub>InOsO<sub>6,</sub> characterized by a band gap of 3.62 eV in the TB-mBJ + U approximation, decreases upon the inclusion of spin–orbit coupling (SOC). This half-metallic property, coupled with the stability of the ferromagnetic phase, makes Ba<sub>2</sub>InOsO<sub>6</sub> particularly suitable for spintronic applications, as it can facilitate efficient spin injection and transport. Elasticity analysis indicates moderate brittleness, while thermoelectric properties, calculated using the Boltzmann transport model, reveal n-type conductivity and notable thermopower, suggesting potential for thermoelectric applications. This work provides a solid foundation for future experimental studies and potential applications in advanced technologies.</div></div>","PeriodicalId":366,"journal":{"name":"Journal of Magnetism and Magnetic Materials","volume":"611 ","pages":"Article 172629"},"PeriodicalIF":2.5,"publicationDate":"2024-10-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142571696","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}
引用次数: 0
Theory analysis and experimental study on magnetic fluid injection of multi-stage magnetic fluid seal 多级磁流体密封的磁流体注入理论分析与实验研究
IF 2.5 3区 材料科学
Journal of Magnetism and Magnetic Materials Pub Date : 2024-10-28 DOI: 10.1016/j.jmmm.2024.172615
Jiawei Liu , Decai Li , Jiahao Dong , Sijia Liu , Jingcheng Cai
{"title":"Theory analysis and experimental study on magnetic fluid injection of multi-stage magnetic fluid seal","authors":"Jiawei Liu ,&nbsp;Decai Li ,&nbsp;Jiahao Dong ,&nbsp;Sijia Liu ,&nbsp;Jingcheng Cai","doi":"10.1016/j.jmmm.2024.172615","DOIUrl":"10.1016/j.jmmm.2024.172615","url":null,"abstract":"<div><div>Magnetic fluid seal (MFS) is one of the most mature applications of magnetic fluid (MF) and is widely used in numerous fields. But challenges arise in maintaining the volume of MF within the sealing gap, particularly under conditions of elevated seal pressure, high rotational speeds, and long-term usage. Injecting MF in multi-stage MFS post-installation poses a notable challenge. The conventional approach of injecting the entire optimal volume into pole teeth faces difficulties, as a portion of the MF tends to adhere to the surface of shaft and pole shoes during installation due to the uneven magnetic field. This study aimed to explore MF injection and devise a method for precisely controlling the MF volume in the sealing gap. To achieve this, a novel concept of multi-stage MFS with larger sealing gaps in specific stages was introduced. The injection and movement of MF were scrutinized through a combination of Computational Fluid Dynamics (CFD) simulations and experimental investigations. The findings from both CFD and experiments unequivocally establish the feasibility of injecting MF in multi-stage MFS. Effective injection is achieved when the inlet pressure increment is maintained below 20 kPa each time. Furthermore, experimental results highlight that the sealing capacity achieved through the injection method surpasses that of the common injection method, particularly for optimal volume MFS.</div></div>","PeriodicalId":366,"journal":{"name":"Journal of Magnetism and Magnetic Materials","volume":"611 ","pages":"Article 172615"},"PeriodicalIF":2.5,"publicationDate":"2024-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142571695","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}
引用次数: 0
Numerical assessment of black powder removal from natural gas using magnetophoresis 利用磁流体从天然气中去除黑火药的数值评估
IF 2.5 3区 材料科学
Journal of Magnetism and Magnetic Materials Pub Date : 2024-10-28 DOI: 10.1016/j.jmmm.2024.172616
Ali Mahmoudi, Majid Mesbah
{"title":"Numerical assessment of black powder removal from natural gas using magnetophoresis","authors":"Ali Mahmoudi,&nbsp;Majid Mesbah","doi":"10.1016/j.jmmm.2024.172616","DOIUrl":"10.1016/j.jmmm.2024.172616","url":null,"abstract":"<div><div>This paper addresses the persistent issue of black powder—solid suspended particles in natural gas streams—that can cause significant damage to gas industry equipment. Despite existing purification processes, black powder remains a challenge due to the limitations of conventional particle removal techniques. To overcome these drawbacks, this study proposes a novel magnetic filter that offers superior efficiency in capturing even submicron particles, significantly reducing maintenance costs and addressing the longstanding problem of black powder accumulation. The properties of black powder and existing separation methods in the natural gas industry are explored, and the performance of the magnetic filter is evaluated through comprehensive numerical analysis using the Discrete Phase Model (DPM). Results demonstrate the filter’s capability to efficiently capture particles as small as 5 µm, with an impressive removal efficiency of 92% for particles as small as 1 µm. This study provides valuable insights into addressing the persistent issue of black powder in natural gas streams and presents a promising solution for its efficient removal, ensuring the long-term integrity and durability of equipment used in natural gas transmission systems.</div></div>","PeriodicalId":366,"journal":{"name":"Journal of Magnetism and Magnetic Materials","volume":"611 ","pages":"Article 172616"},"PeriodicalIF":2.5,"publicationDate":"2024-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142537484","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}
引用次数: 0
Broadband microwave absorption and electromagnetic properties of Gd–Al–Co-doped M−type barium hexaferrite in 2–18 GHz range 掺杂 Gd-Al-Co 的 M 型六价钡铁氧体在 2-18 GHz 范围内的宽带微波吸收和电磁特性
IF 2.5 3区 材料科学
Journal of Magnetism and Magnetic Materials Pub Date : 2024-10-24 DOI: 10.1016/j.jmmm.2024.172609
Weihua Liao, Kai Huang, Wenwen Xu, Jiangying Yu, Ping Li, Jinrong Xu
{"title":"Broadband microwave absorption and electromagnetic properties of Gd–Al–Co-doped M−type barium hexaferrite in 2–18 GHz range","authors":"Weihua Liao,&nbsp;Kai Huang,&nbsp;Wenwen Xu,&nbsp;Jiangying Yu,&nbsp;Ping Li,&nbsp;Jinrong Xu","doi":"10.1016/j.jmmm.2024.172609","DOIUrl":"10.1016/j.jmmm.2024.172609","url":null,"abstract":"<div><div>Gd–Al–Co-doped BaFe<sub>12−3x</sub>(GdAlCo)<sub>x</sub>O<sub>19</sub> (x = 0, 0.1, 0.2, 0.3, 0.4) was synthesized via the hydrothermal method. We performed comprehensive characterization using XRD, SEM, BET, VSM, XPS, and VNA techniques to explore the impact of substituting magnetic Co<sup>2+</sup>, Gd<sup>3+</sup>, and nonmagnetic Al<sup>3+</sup> for Fe<sup>3+</sup> on the morphology, specific surface area, magnetic, and microwave absorption (MWA) properties of BaFe<sub>12−3x</sub>(GdAlCo)<sub>x</sub>O<sub>19</sub>. Investigating the MWA properties of BaFe<sub>12−3x</sub>(GdAlCo)<sub>x</sub>O<sub>19</sub> in the 2–18 GHz range, we find that all doped samples demonstrate excellent MWA characteristics. The sample BaFe<sub>11.1</sub>(GdAlCo)<sub>0.3</sub>O<sub>19</sub> achieves a minimum reflection loss (RL<sub>min</sub>) of − 48.13 dB at a thickness of 2.07 mm, indicating an absorption of over 99 % of incident microwaves. The effective absorption bandwidth (EAB) for all four groups of doped samples exceeds 5.98 GHz. Notably, the x  = 0.1 samples reach an EAB of 9.15 GHz at only 2.0 mm thickness, covering most of the X-band and the entire Ku band. Gd-Al-Co co doping of BaFe<sub>12</sub>O<sub>19</sub> not only improves its reflection loss ability, but also increases its absorption bandwidth. Improved the drawbacks of narrow bandwidth and poor loss capability in BaFe<sub>12</sub>O<sub>19</sub>. Consequently, BaFe<sub>12−3x</sub>(GdAlCo)<sub>x</sub>O<sub>19</sub> material shows significant potential for practical applications.</div></div>","PeriodicalId":366,"journal":{"name":"Journal of Magnetism and Magnetic Materials","volume":"612 ","pages":"Article 172609"},"PeriodicalIF":2.5,"publicationDate":"2024-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142660679","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}
引用次数: 0
Single-molecule Magnets (SMM) spin channels connecting FeMn antiferromagnet and NiFe ferromagnetic electrodes of a tunnel junction 连接隧道结的铁锰反铁磁体和镍铁铁磁电极的单分子磁体 (SMM) 自旋通道
IF 2.5 3区 材料科学
Journal of Magnetism and Magnetic Materials Pub Date : 2024-10-24 DOI: 10.1016/j.jmmm.2024.172608
Babu Ram Sankhi , Erwan Peigney , Hayden Brown , Pius Suh , Carlos Rojas-Dotti , José Martínez-Lillo , Pawan Tyagi
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