Gopika C.T. , Prajisha K.P. , Apoorva Kaul , Umesh P. Borole , Jakeer Khan , Bhagaban Behera , P. Chowdhury
{"title":"Enhancement of spin valve GMR sensor’s sensitivity with [Ta/NiFe]n on-chip magnetic flux concentrator","authors":"Gopika C.T. , Prajisha K.P. , Apoorva Kaul , Umesh P. Borole , Jakeer Khan , Bhagaban Behera , P. Chowdhury","doi":"10.1016/j.jmmm.2025.172812","DOIUrl":"10.1016/j.jmmm.2025.172812","url":null,"abstract":"<div><div>This study uses an integrated on-chip magnetic flux concentrator to explore the sensitivity enhancement of synthetic antiferromagnetic spin Valve (SV-SAF) sensors. Theoretical simulation on MFC indicates that a high magnetic gain factor up to 50 can be achieved with a lower air gap of <span><math><mrow><mn>20</mn><mspace></mspace><mi>μ</mi><mi>m</mi></mrow></math></span> and thicker, high permeability MFC material. In this report, a laminated film of [Ta/NiFe]<span><math><msub><mrow></mrow><mrow><mi>n</mi></mrow></msub></math></span> of thickness <span><math><mo>∼</mo></math></span> <span><math><mrow><mn>1</mn><mspace></mspace><mi>μ</mi><mi>m</mi></mrow></math></span> was sputter deposited to achieve high permeability and low coercivity films. The magnetic gain factor was estimated by measuring the properties of the transfer curve of a single GMR-SV resistor embedded in the air gap. The results show that the magnetic gain of 25 and 46 were achieved by using 40 and <span><math><mrow><mn>20</mn><mspace></mspace><mi>μ</mi><mi>m</mi></mrow></math></span> air gap respectively. Further studies on Wheatstone bridge configuration reveal that the sensitivity of the spin valve can be improved to 10.7 mV/V/G in an operating field range of <span><math><mo>±</mo></math></span> 0.5 G. These sensors have potential applications in low-field detection for healthcare applications.</div></div>","PeriodicalId":366,"journal":{"name":"Journal of Magnetism and Magnetic Materials","volume":"616 ","pages":"Article 172812"},"PeriodicalIF":2.5,"publicationDate":"2025-01-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143165390","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}
{"title":"Modeling electromagnetic radiation induced by magnetoelastic waves in thickness shear mode","authors":"Guokai Xu , Shaoqiu Xiao , Yan Li , Yunliang Long","doi":"10.1016/j.jmmm.2025.172833","DOIUrl":"10.1016/j.jmmm.2025.172833","url":null,"abstract":"<div><div>Acoustically actuated magnetoelectric (ME) antenna is a novel electrically small antenna (ESA) technology currently attracting significant attention. It is anticipated to break through the limitations of electromagnetic (EM) wavelength, leading to a reduction in antenna size by orders of magnitude. However, modeling and analyzing ME antennas is always challenging, especially when considering micromagnetics and magnetoelastic coupling (MEC). In this work, the cellular model of the ME magnon-polaron antenna is proposed for the first time. Coupling the elastic, spin, and electromagnetic (EM) waves enables the conversion from radio frequency (RF) voltage to magnetoelastic waves (MEWs) to EM radiation. Ferromagnetic resonance (FMR) enhances the antenna’s radiation efficiency, and the magnon-polaron splits the acoustic resonance frequency. The reconfiguration of the antenna’s resonance and polarization characteristics can be achieved through the adjustment of the bias magnetic field. The blind spots in the radiation efficiency spectrum arise from either the standing spin waves or the polarization orthogonality between the spin and elastic waves. The modeling and analysis technique helps improve the design and boost the radiation performance of magnon-polaron antennas.</div></div>","PeriodicalId":366,"journal":{"name":"Journal of Magnetism and Magnetic Materials","volume":"616 ","pages":"Article 172833"},"PeriodicalIF":2.5,"publicationDate":"2025-01-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143164786","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}
A. Samih , E. Salmani , Hussein. Sabbah , R. El Fdil , Z. Fadil , Fohad Mabood Husain , Seong Cheol Kim , Chaitany Jayprakash Raorane
{"title":"Investigating Half-Metallic behavior of doped tin-carbide Sn(1-x)TM(x)C with TM = V, Cr, Mn and Fe: LDA and LDA + U analysis","authors":"A. Samih , E. Salmani , Hussein. Sabbah , R. El Fdil , Z. Fadil , Fohad Mabood Husain , Seong Cheol Kim , Chaitany Jayprakash Raorane","doi":"10.1016/j.jmmm.2025.172829","DOIUrl":"10.1016/j.jmmm.2025.172829","url":null,"abstract":"<div><div>This paper investigates the structural, electronic, and magnetic properties of SnC doped with transition metals (TMs) such as V, Cr, Mn, and Fe. The LDA and LDA + U approximations were employed to study the electronic properties of TM-doped SnC. Our findings demonstrate half-metallic behavior and ferromagnetism in these systems. We also calculated the Curie temperature for various TM concentrations and confirmed the mechanical and thermal stability of TM-doped SnC. Moreover, we extend zero-temperature first-principles DFT calculations of TM-doped SnC to finite-temperature Monte Carlo simulations using the Heat Bath algorithm to determine the curie temperature of Sn<sub>0</sub>.<sub>90</sub>TM<sub>0</sub>.<sub>10</sub>C (TM = V, Cr, Mn).These results enhance our understanding of doped SnC and provide valuable insights into its potential applications in advanced spintronic devices and nanotechnologies.</div></div>","PeriodicalId":366,"journal":{"name":"Journal of Magnetism and Magnetic Materials","volume":"616 ","pages":"Article 172829"},"PeriodicalIF":2.5,"publicationDate":"2025-01-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143165391","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}
Xiao-Xue Yang , Huiting Li , Je-Ho Shim, Xue-Feng Zhang, Xiao-Ping Ma, Junyan Gao, Xing Ri Jin, Hong-Guang Piao
{"title":"Dynamic pinning and phase stability of transverse domain walls in asymmetric tie-shaped nanowires for spintronic applications","authors":"Xiao-Xue Yang , Huiting Li , Je-Ho Shim, Xue-Feng Zhang, Xiao-Ping Ma, Junyan Gao, Xing Ri Jin, Hong-Guang Piao","doi":"10.1016/j.jmmm.2025.172828","DOIUrl":"10.1016/j.jmmm.2025.172828","url":null,"abstract":"<div><div>The dynamic control and phase stability of transverse domain walls (TDWs) in nanowires are pivotal for advancing spintronic technologies. This study uses micromagnetic simulations to investigate TDWs in asymmetric Tie-shaped permalloy nanowires (T-NWs). By exploiting the continuously varying width of T-NWs, we uncover the intricate mechanisms of TDW pinning and motion under applied magnetic fields. Our findings highlight stable pinning processes and identify critical instabilities that herald phase transitions to vortex domain walls (VDWs). We systematically analyze non-equilibrium energy dynamics, including exchange, anisotropy, and Zeeman energies, and we elucidate the energy dissipation pathways and their role in TDW stabilization. The results reveal that TDW phase stability is highly sensitive to geometric asymmetry, providing key insights for optimizing nanowire designs to enhance TDW control. These insights pave the way for more efficient spintronic devices, particularly in applications requiring high-speed domain wall manipulation and robust magnetic state retention.</div></div>","PeriodicalId":366,"journal":{"name":"Journal of Magnetism and Magnetic Materials","volume":"616 ","pages":"Article 172828"},"PeriodicalIF":2.5,"publicationDate":"2025-01-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143165400","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}
Ranbin Wang , Zhanfan Jin , Wenhui Guo , You Wu , Jili Jia , Yang Shao , Na Chen , Kefu Yao
{"title":"Effects of magnetic volume fraction induced by compaction pressure on magnetic properties of FeBCPSiMoCr-based soft magnetic composites","authors":"Ranbin Wang , Zhanfan Jin , Wenhui Guo , You Wu , Jili Jia , Yang Shao , Na Chen , Kefu Yao","doi":"10.1016/j.jmmm.2025.172832","DOIUrl":"10.1016/j.jmmm.2025.172832","url":null,"abstract":"<div><div>The development of Fe-based glassy powders and low-loss soft magnetic composites (SMCs) is a major challenge for advancing high-frequency and miniaturized electronic devices. In the present work, highly spherical glassy powders from a new Fe<sub>75</sub>B<sub>7</sub>C<sub>7</sub>P<sub>7</sub>Si<sub>3</sub>Mo<sub>0.5</sub>Cr<sub>0.5</sub> alloy with high glass-forming ability (GFA) have been successfully prepared by a gas–water combined atomization method. The effects of compaction pressure on the magnetic properties of the corresponding SMCs were elucidated. High compaction pressure could effectively increase the magnetic volume fraction of the SMCs, thereby enhancing the effective permeability (<em>μ</em><sub>e</sub>). Additionally, the reduced total core loss (<em>P</em><sub>cv</sub>) could be mainly attributed to the reduced hysteresis loss associated with the decreased coercivity. At the maximum compaction pressure of 2000 MPa, the SMC exhibits optimal comprehensive performance, with a stable <em>μ</em><sub>e</sub> of 31.0 up to 1 MHz, a DC-Bias performance of 75.2 % under a 100 Oe field, and a <em>P</em><sub>cv</sub> of 5819 kW/m<sup>3</sup> (100 mT, 500 kHz). These results could expedite the development of new low-loss SMCs.</div></div>","PeriodicalId":366,"journal":{"name":"Journal of Magnetism and Magnetic Materials","volume":"616 ","pages":"Article 172832"},"PeriodicalIF":2.5,"publicationDate":"2025-01-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143164779","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}
{"title":"Modeling magnetic separation of metal ions in aqueous solutions","authors":"Petru Andrei, Nicholas Carlstedt, Pranathi Brungi","doi":"10.1016/j.jmmm.2025.172818","DOIUrl":"10.1016/j.jmmm.2025.172818","url":null,"abstract":"<div><div>Although the techniques for the magnetic separation of large (micrometer size) ferromagnetic and paramagnetic particles are well developed and commercially used on a large scale, the magnetic separation of nanoparticles is not well studied. In this article, we develop a mathematical model to describe the transport of small paramagnetic and diamagnetic particles in liquids under a non-uniform magnetic field. Special emphasis is given to thermal diffusion, which is shown to play an important role in the transport of nanoparticles. The model describes the magnetic particles and the solvent as two interpenetrating continua: the magnetic particle continuum, which interacts with the external magnetic field, lacks inertia, and moves through the solvent while experiencing a force of resistance from the solvent; and the solvent continuum which is assumed non-magnetic and inert. The two continua are described using the Navier-Stokes and drift–diffusion equations, respectively. Using our model, we analyze the effects of drag, gravitation, thermal diffusion and magnetophoresis on the dynamics of the particles and look at the conditions under which these phenomena dominate their transport properties. The model is in good qualitative agreement with experiments published in the literature.</div></div>","PeriodicalId":366,"journal":{"name":"Journal of Magnetism and Magnetic Materials","volume":"616 ","pages":"Article 172818"},"PeriodicalIF":2.5,"publicationDate":"2025-01-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143164785","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}
{"title":"Ferromagnetism in In2O3-based nanostructures: A review on structure, shape, electronic structure, magnetic properties, DFT modeling and applications","authors":"Manikandan Dhamodaran , Rahul Kumar Yadav , Rajeev Gupta","doi":"10.1016/j.jmmm.2025.172815","DOIUrl":"10.1016/j.jmmm.2025.172815","url":null,"abstract":"<div><div>In<sub>2</sub>O<sub>3</sub> is extensively studied as a wide-band gap semiconductor because of its numerous uses in spintronics and optoelectronics devices. Recently, researchers have primarily focused on fine-tuning the functional characteristics of nanoscale In<sub>2</sub>O<sub>3</sub> semiconductors by manipulating their size, shape, and the local microenvironment of dopants. In this review, we highlight the decisive investigation of structure–property correlation, shape-dependent, and doping-induced magnetic properties of In<sub>2</sub>O<sub>3</sub> nanostructures. First, we critically discussed the various synthesis methods utilized to prepare the different In<sub>2</sub>O<sub>3</sub>-based nanostructures. We then systematically investigated the impact of different shapes of In<sub>2</sub>O<sub>3,</sub> including nanoparticles (0D), nanowires/nanorods (1D/2D), 3D nanoflowers, and thin film structures on the magnetic characteristics. In addition to pristine In<sub>2</sub>O<sub>3</sub>, we emphasize the recent advances in the stimulus of metal incorporation on shape and magnetic features of In<sub>2</sub>O<sub>3</sub> were investigated. The electronic band structure and magnetic properties of pure and metal-substituted In<sub>2</sub>O<sub>3</sub> were analyzed using density functional theory. A distinctive section is dedicated to the growth mechanism of In<sub>2</sub>O<sub>3</sub> nanostructures, the basis of ferromagnetism, and some relevant technological applications. Finally, a brief outlook and challenges were discussed on realizing the basis and switching of ferromagnetism.</div></div>","PeriodicalId":366,"journal":{"name":"Journal of Magnetism and Magnetic Materials","volume":"616 ","pages":"Article 172815"},"PeriodicalIF":2.5,"publicationDate":"2025-01-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143164778","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}
Shan Huang , Xiaojun Sun , Zilong Wang , Xiao Lin , Qinjia Wang , Yuanfei Yang , Tianping Tang , Kaiwen Wu , Wenlong Yan , Yang Luo , Dunbo Yu , Xiaowei Huang
{"title":"Optimization of grain boundary diffusion in Nd-Ce-Fe-B magnets through CeFe2 phase","authors":"Shan Huang , Xiaojun Sun , Zilong Wang , Xiao Lin , Qinjia Wang , Yuanfei Yang , Tianping Tang , Kaiwen Wu , Wenlong Yan , Yang Luo , Dunbo Yu , Xiaowei Huang","doi":"10.1016/j.jmmm.2025.172788","DOIUrl":"10.1016/j.jmmm.2025.172788","url":null,"abstract":"<div><div>The REFe<sub>2</sub> phase in Ce-containing Nd-Ce-Fe-B magnets is considered detrimental to magnetic properties due to its soft magnetism, and the presence of the CeFe<sub>2</sub> phase hinders the diffusion of heavy rare earth elements. In this study, grain boundary diffusion (GBD) treatment was performed on commercial N40 sintered Nd-Ce-Fe-B magnets using Tb and Tb<sub>70</sub>Cu<sub>30</sub> alloys, respectively. The results indicate that the CeFe<sub>2</sub> phases appear at the grain boundaries during grain boundaries diffusion, but there is a significant difference in the distribution and quantity of the CeFe<sub>2</sub> phase between Tb GBD magnets and Tb<sub>70</sub>Cu<sub>30</sub> GBD magnets. Cu atoms are more likely to bind with Ce in the grain boundary phase, thereby suppressing the formation of CeFe<sub>2</sub> phase and improving the diffusion effect of Tb in Ce-containing magnets. Additionally, Cu broadens the grain boundaries, allowing for deeper diffusion of Tb. Although the substitution of Tb (30 wt%) by Cu in the Tb<sub>70</sub>Cu<sub>30</sub> alloy, the Tb<sub>70</sub>Cu<sub>30</sub> GBD magnet still achieves significant coercivity enhancement, nearly as well as the Tb GBD magnet. This work provides new prospects for the development of Nd-Ce-Fe-B magnets treated with grain boundary diffusion.</div></div>","PeriodicalId":366,"journal":{"name":"Journal of Magnetism and Magnetic Materials","volume":"616 ","pages":"Article 172788"},"PeriodicalIF":2.5,"publicationDate":"2025-01-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143202273","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}
{"title":"Microwave absorption and magnetic properties of Ni-NiO-GO nanocomposites","authors":"Manas Kumar Mondal , Nupur Bhakta , Madhumita Dalal , Sukhendu Sadhukhan , Anupam Banerjee , Chandi Charan Dey , Souvick Das , P.K. Chakrabarti","doi":"10.1016/j.jmmm.2025.172819","DOIUrl":"10.1016/j.jmmm.2025.172819","url":null,"abstract":"<div><div>Nanocomposite of Ni-NiO was synthesized using sol–gel technique. To enhance the synergistic effect the as-prepared nanocomposite was incorporated in graphene oxide (GO). Recorded X-ray diffractograms and their Rietveld refinement confirmed the desired crystallographic phase of the nanocomposite. Results and analyses of transmission electron microscopy and Raman spectroscopy established the presence of GO phase in Ni-NiO-GO. Conductivity measurements (J vs E curve) indicate the enhancement of conductivity due to which shielding property is enhanced in Ni-NiO-GO compared to Ni-NiO. Magnetic properties were investigated in detail and analysis of magnetic data showed that majority of the nanoparticles are in ferrimagnetic order state together with a presence of insignificant fraction of ferrimagnetic nanoparticles. Observed magnetic loops were also fitted theoretically. Interestingly, the microwave absorption suggested that shielding property was enhanced as a whole compared to Ni-NiO which is quite interesting for applications in shielding devices.</div></div>","PeriodicalId":366,"journal":{"name":"Journal of Magnetism and Magnetic Materials","volume":"616 ","pages":"Article 172819"},"PeriodicalIF":2.5,"publicationDate":"2025-01-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143164784","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}
{"title":"Flexible ultrawide band frequency selective surface for shielding applications","authors":"Naveena Meka, Shambavi Krishnan","doi":"10.1016/j.jmmm.2025.172807","DOIUrl":"10.1016/j.jmmm.2025.172807","url":null,"abstract":"<div><div>This article presents a miniaturized angularly stable wideband Frequency Selective Surface (FSS) for shielding applications. The unique feature of the proposed FSS is its wide-angle and polarization independent specular shielding over a broad band for both TE and TM polarization. The shield consists of four FSS combined on a Rogers 5880 substrate of relative permittivity 2.2 and thickness 0.25 mm. FSS is combined to improve the polarization and angular stability for wide incidence angles. The dimension of the shielding unit cell is 0.42<em>λg</em> × 0.42<em>λg, λg</em> is the guided wavelength. Both planar and conformal shields were analyzed, fabricated and tested for shield effectiveness in the anechoic chamber. The proposed FSS exhibits ultra-wideband (3.7–15.5 GHz) characteristics with shield effectiveness of 67 dB at 8.7 GHz and stable response up to 75° incidence angle due to its smaller size, and fourfold symmetric structure. Simulated and measured transmission responses are in good agreement and hence well suited for the shielding upper WLAN band, sub 6 GHz 5G band, and C/Ku band for satellite communication. These bands find its application in shielding the upper WLAN band, sub 6 GHz 5G band, and C/Ku band for satellite communication.</div></div>","PeriodicalId":366,"journal":{"name":"Journal of Magnetism and Magnetic Materials","volume":"616 ","pages":"Article 172807"},"PeriodicalIF":2.5,"publicationDate":"2025-01-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143164782","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}