IEEE Magnetics Letters最新文献_第2页

Features and Peculiarities of Gate-Voltage Modulation of Spin-Orbit Interaction in FeB Nanomagnets: Insights Into the Physical Origins of the Voltage-Controlled Magnetic Anisotropy Effect FeB纳米磁体中自旋轨道相互作用的栅极电压调制的特征和特性：电压控制磁各向异性效应物理根源的见解

IF 1.1 4区物理与天体物理

IEEE Magnetics Letters Pub Date : 2025-04-14 DOI: 10.1109/LMAG.2025.3560858

Vadym Zayets

{"title":"Features and Peculiarities of Gate-Voltage Modulation of Spin-Orbit Interaction in FeB Nanomagnets: Insights Into the Physical Origins of the Voltage-Controlled Magnetic Anisotropy Effect","authors":"Vadym Zayets","doi":"10.1109/LMAG.2025.3560858","DOIUrl":"https://doi.org/10.1109/LMAG.2025.3560858","url":null,"abstract":"This letter systematically investigates the fundamental mechanisms driving the voltage-controlled magnetic anisotropy (VCMA) effect, with a focus on the dependencies of the anisotropy field and the strength of spin-orbit (SO) interaction on gate voltage, measured in Ta/FeB/MgO nanomagnets. Our findings reveal an intriguing opposite polarity in the gate-voltage dependencies of the anisotropy field and the coefficient of SO interaction across all studied nanomagnets. This discovery challenges the prevailing assumption that SO interaction is the primary contributor to the VCMA effect, instead suggesting that gate-voltage modulation of magnetization is likely the dominant factor, as its polarity aligns with the observed modulation of anisotropy. The modulation of magnetic anisotropy is governed by two major contributions with opposite polarities, which tend to counterbalance each other, reducing the overall VCMA effect. Optimizing this balance could significantly enhance the VCMA effect, offering a promising avenue for broadening its applications. In addition, our measurements confirm that gate voltage does not modulate the in-plane component of spin accumulation, providing further insights into the underlying mechanisms of the VCMA effect.","PeriodicalId":13040,"journal":{"name":"IEEE Magnetics Letters","volume":"16 ","pages":"1-4"},"PeriodicalIF":1.1,"publicationDate":"2025-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144108338","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Size Dependence of the Read Voltage and Electrical Diameter of STT MRAM Cells STT MRAM电池读电压和电径的尺寸依赖性

IF 1.1 4区物理与天体物理

IEEE Magnetics Letters Pub Date : 2025-04-14 DOI: 10.1109/LMAG.2025.3560889

Goran Mihajlović;Wonjoon Jung;Noraica Dávila;Jeffrey Lille;Michael Tran;Jordan A. Katine;Michael K. Grobis

引用次数: 0

Fast Acquisition of Sensor Array Geometry of Whole-Head Magnetoencephalograph Systems Using a Neural Network 基于神经网络的全头脑磁仪传感器阵列几何结构快速采集

IF 1.1 4区物理与天体物理

IEEE Magnetics Letters Pub Date : 2025-04-14 DOI: 10.1109/LMAG.2025.3560886

Yoshiaki Adachi;Daisuke Oyama;Gen Uehara

{"title":"Fast Acquisition of Sensor Array Geometry of Whole-Head Magnetoencephalograph Systems Using a Neural Network","authors":"Yoshiaki Adachi;Daisuke Oyama;Gen Uehara","doi":"10.1109/LMAG.2025.3560886","DOIUrl":"https://doi.org/10.1109/LMAG.2025.3560886","url":null,"abstract":"Acquiring position, orientation, and sensitivity of magnetometers in a helmet-shaped sensor array is crucial for accurate current source reconstruction in magnetoencephalography. To determine these parameters for each magnetometer, we utilize a spherical calibration coil array. In our previous study, the position and orientation of each magnetometer were determined as the solution of an inverse problem through a numerical search that minimized the difference between the theoretical magnetic field signals from each coil and the measured signals detected by the magnetometer. In this study, we applied a deep neural network to estimate the position and orientation of each magnetometer in the helmet-shaped sensor array without solving the inverse problem. A total of 223 million pairs of a given magnetometer's five parameters (<italic>x, <italic>y, <italic>z, <italic>θ, and <italic>ϕ) and the corresponding theoretical magnetic field signals from the coils were used to train the neural network. The training process required approximately 53 h using a commercially available GPU-equipped computer. The trained neural network was then applied to acquire the sensor geometry from magnetic field data obtained during a conventional calibration procedure for a 160-channel whole-head magnetoencephalograph system using a spherical calibration coil array. The position and orientation of each magnetometer estimated by this method deviated by an average of 0.65 mm and 0.51°, respectively, from those obtained via the conventional inverse problem approach. The acquisition of the geometry for all 160 magnetometers required less than 8 ms. With such high-speed acquisition, this approach opens possibilities for future applications in acquiring positional information of wearable sensor arrays whose structures change in real time.","PeriodicalId":13040,"journal":{"name":"IEEE Magnetics Letters","volume":"16 ","pages":"1-5"},"PeriodicalIF":1.1,"publicationDate":"2025-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10964712","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144179108","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Voltage-Modulated Magneto-Dynamics in Spin Hall Nano-Oscillators 自旋霍尔纳米振荡器的调压磁动力学

IF 1.1 4区物理与天体物理

IEEE Magnetics Letters Pub Date : 2025-03-28 DOI: 10.1109/LMAG.2025.3555942

Linrong Yao;Hongchao Xie;Bin Hu;Sheng Jiang

引用次数: 0

YIG/CoFeB Bilayer Magnonic Isolator YIG/CoFeB双层磁振子

IF 1.1 4区物理与天体物理

IEEE Magnetics Letters Pub Date : 2025-03-17 DOI: 10.1109/LMAG.2025.3551990

Noura Zenbaa;Khrystyna O. Levchenko;Jaganandha Panda;Kristýna Davídková;Moritz Ruhwedel;Sebastian Knauer;Morris Lindner;Carsten Dubs;Qi Wang;Michal Urbánek;Philipp Pirro;Andrii V. Chumak

{"title":"YIG/CoFeB Bilayer Magnonic Isolator","authors":"Noura Zenbaa;Khrystyna O. Levchenko;Jaganandha Panda;Kristýna Davídková;Moritz Ruhwedel;Sebastian Knauer;Morris Lindner;Carsten Dubs;Qi Wang;Michal Urbánek;Philipp Pirro;Andrii V. Chumak","doi":"10.1109/LMAG.2025.3551990","DOIUrl":"https://doi.org/10.1109/LMAG.2025.3551990","url":null,"abstract":"We demonstrate a magnonic isolator based on a bilayer structure of yttrium iron garnet (YIG) and cobalt iron boron (CoFeB). The bilayer exhibits pronounced nonreciprocal spin-wave propagation, enabled by dipolar coupling and the magnetic properties of the two layers. The YIG layer provides low damping and efficient spin-wave propagation, whereas the CoFeB layer introduces strong magnetic anisotropy, critical for achieving the isolator functionality. Experimental results, supported by numerical simulations, show unidirectional propagation of magneto-static surface spin waves, significantly suppressing backscattered waves. This behavior was confirmed through wavevector-resolved and microfocused Brillouin light scattering measurements and is supported by numerical simulations. The developed YIG/SiO<inline-formula><tex-math>$_{2}$</tex-math></inline-formula>/CoFeB bilayer magnonic isolator demonstrates the feasibility of leveraging nonreciprocal spin-wave dynamics for functional magnonic devices, paving the way for energy-efficient, wave-based signal processing technologies.","PeriodicalId":13040,"journal":{"name":"IEEE Magnetics Letters","volume":"16 ","pages":"1-5"},"PeriodicalIF":1.1,"publicationDate":"2025-03-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10930529","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143865306","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Ready-to-Use Composite Fused Deposition Modeling Filaments Produced With Polylactic Acid and Recycled Nd–Fe–B Nanocrystalline Powder for Additive Manufacturing of Bonded Magnets 用聚乳酸和回收的Nd-Fe-B纳米晶粉末制备用于粘结磁体增材制造的即用复合熔融沉积建模长丝

IF 1.1 4区物理与天体物理

IEEE Magnetics Letters Pub Date : 2025-03-14 DOI: 10.1109/LMAG.2025.3551243

Gabriel M. Vieira;Marcelo A. Rosa;Paulo A. P. Wendhausen;Maximiliano D. Martins

{"title":"Ready-to-Use Composite Fused Deposition Modeling Filaments Produced With Polylactic Acid and Recycled Nd–Fe–B Nanocrystalline Powder for Additive Manufacturing of Bonded Magnets","authors":"Gabriel M. Vieira;Marcelo A. Rosa;Paulo A. P. Wendhausen;Maximiliano D. Martins","doi":"10.1109/LMAG.2025.3551243","DOIUrl":"https://doi.org/10.1109/LMAG.2025.3551243","url":null,"abstract":"Fused deposition modeling (FDM) is an additive manufacturing technique that has become widely used in many fields of engineering and has recently proven to be suitable for producing complex, net-shaped bonded Nd–Fe–B magnets. At the same time, recycling end-of-life magnets has been an emerging concern due to their increasing presence in current technologies and the intrinsic scarcity of rare-Earth elements, such as neodymium and praseodymium. Here, we investigated the feasibility of using recycled nanocrystalline Nd–Fe–B powders, obtained from a hydrogenation–disproportionation–desorption–recombination (HDDR) process in the preparation of FDM feedstock and subsequent printing of magnetic parts. Recycled magnetic powder was mixed with polylactic acid and extruded into filaments containing increasing volume fractions of magnetic powder. It was possible to obtain filaments containing from 6.7% to 23.6% in volume (30.4 to 65.2 wt.%) of the magnetic powder, from which parts could be printed, reaching maximum coercivity (<italic>Hcj) of 707.7 ± 3.5 kA/m, maximum remanence (<italic>Br) of 84.5 ± 0.4 mT, maximum energy product (<italic>BHmax) of 1.3 kJ/m3, and average part porosity of 42 ± 8%. Coercivity loss of about 8.6% was observed in the printed parts compared to the recycled powder (750±75 kA/m). Aging experiments showed that such loss may be a combined effect of thermal and oxidation effects of the magnetic particles during the additive manufacturing processing. The present work has demonstrated the achievement of ready-to-use, high-coercivity FDM filaments, and 3-D-printed parts using recycled Nd–Fe–B HDDR powders.","PeriodicalId":13040,"journal":{"name":"IEEE Magnetics Letters","volume":"16 ","pages":"1-5"},"PeriodicalIF":1.1,"publicationDate":"2025-03-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143856196","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Tuning Magnetic Behavior of Lanthanum-Substituted Gd3Fe5O12: An Experimental Study 镧取代Gd3Fe5O12调谐磁性能的实验研究

IF 1.1 4区物理与天体物理

IEEE Magnetics Letters Pub Date : 2025-03-14 DOI: 10.1109/LMAG.2025.3551266

Aakansha Aakansha;Seenipandian Ravi

{"title":"Tuning Magnetic Behavior of Lanthanum-Substituted Gd3Fe5O12: An Experimental Study","authors":"Aakansha Aakansha;Seenipandian Ravi","doi":"10.1109/LMAG.2025.3551266","DOIUrl":"https://doi.org/10.1109/LMAG.2025.3551266","url":null,"abstract":"This letter covers the structural and magnetic properties of lanthanum-substituted gadolinium iron garnet (GIG) (Gd3-<italic>xLa<italic>xFe5O12), where the La ion was substituted at the Gd site. X-ray diffraction analysis suggested that the synthesized samples possess cubic crystal structure with an increase in lattice constant with La substitution. The crystallite size was estimated through the Williamson–Hall plot analysis and found to increase from 50.577 for <inline-formula><tex-math>${x}$</tex-math></inline-formula> = 0 to 67.343 nm for <inline-formula><tex-math>${x}$</tex-math></inline-formula> = 0.4. The room temperature magnetization value was increasing from 0.162 to 2.536 emu/g from pure to La-substituted GIG. These materials display a ferrimagnetic to paramagnetic phase transition as high temperature rose from 565 to 573 K, which is attributed to the high superexchange interaction between Fe3+ ions. In addition to transition, temperature magnetic compensation was also observed below room temperature. The coercivity of the samples was estimated from the room temperature hysteresis curve, which shows soft ferrimagnetic behavior. The stable crystal structure, low magnetic compensation, low coercive field, and high transition temperature make these materials suitable for communication devices.","PeriodicalId":13040,"journal":{"name":"IEEE Magnetics Letters","volume":"16 ","pages":"1-5"},"PeriodicalIF":1.1,"publicationDate":"2025-03-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143830542","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

A Tunable Magnetic Bias Circuit With Zero Static Power Consumption 一种零静态功耗的可调谐偏磁电路

IF 1.1 4区物理与天体物理

IEEE Magnetics Letters Pub Date : 2025-02-18 DOI: 10.1109/LMAG.2025.3541915

Yixiao Ding;Xuan Wang;Mark G. Allen

{"title":"A Tunable Magnetic Bias Circuit With Zero Static Power Consumption","authors":"Yixiao Ding;Xuan Wang;Mark G. Allen","doi":"10.1109/LMAG.2025.3541915","DOIUrl":"https://doi.org/10.1109/LMAG.2025.3541915","url":null,"abstract":"Quasi-static magnetic fields can be used to modulate the magnetic and electrical properties of many magnetic materials, thereby enabling the operation of various magnetic devices, such as multiferroic magnetic field sensors and ferro/ferrimagnetic magneto-static wave filters. We present a magnetic circuit designed to produce a tunable dc magnetic bias field and detail its operating principle. The magnitude of the bias field can be electrically tuned to achieve a desired magnetic field; when not being switched, the achieved field is maintained with zero static power consumption. The magnetic circuit comprises two distinct types of permanent magnets: an NdFeB magnet with relatively high coercivity and an AlNiCo V magnet with relatively low coercivity combined with a tuning coil for adjusting its magnetization. Soft magnetic yoke pieces link the permanent magnets and also define an air gap. Pulses of current through the coil will adjust the remanence of the AlNiCo magnet, thereby changing the flux and field in the air gap. A magnetic bias circuit with a compact volume of 0.27 cm3 has been constructed, providing an adjustable dc magnetic field with a tuning range of 3.7 to 288.5 mT within a 1 mm air gap.","PeriodicalId":13040,"journal":{"name":"IEEE Magnetics Letters","volume":"16 ","pages":"1-5"},"PeriodicalIF":1.1,"publicationDate":"2025-02-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143637904","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

About the Cover 关于封面

IF 1.1 4区物理与天体物理

IEEE Magnetics Letters Pub Date : 2025-02-12 DOI: 10.1109/LMAG.2024.3510493

引用次数: 0

Magneto-Elastic Coupling of Surface Spin and Surface Acoustic Waves 表面自旋与表面声波的磁弹性耦合

IF 1.1 4区物理与天体物理

IEEE Magnetics Letters Pub Date : 2025-01-30 DOI: 10.1109/LMAG.2025.3536936

Nicholas Homrocky;Cody Trevillian;Vasyl Tyberkevych

{"title":"Magneto-Elastic Coupling of Surface Spin and Surface Acoustic Waves","authors":"Nicholas Homrocky;Cody Trevillian;Vasyl Tyberkevych","doi":"10.1109/LMAG.2025.3536936","DOIUrl":"https://doi.org/10.1109/LMAG.2025.3536936","url":null,"abstract":"Nonreciprocal propagation of surface acoustic waves (SAWs) may be achieved through magneto-elastic coupling with surface spin waves (SSWs). Here, we studied theoretically SAW–SSW coupling in yttrium–iron garnet (YIG)/ gadolinium–gallium garnet (GGG) bilayers magnetized in-plane at an oblique angle to the direction of wave propagation. An expression for the coupling rate that considers actual thickness profiles of both waves has been derived. The effects of the SAW–SSW coupling are most pronounced at the crossing point of the SAW and SSW spectra, which, for typical experimental parameters, occurs at a frequency of about 2 GHz and wavelength 2 µm. Under these conditions, the coupling rate for SSWs localized near the free surface of the YIG layer weakly depends on system parameters and exceeds 25 MHz. In contrast, for the opposite direction of wave propagation, when the SSW is localized near the YIG/GGG interface, the coupling rate rapidly decreases with the increase of YIG thickness, and strong nonreciprocity of the coupling is observed for thicknesses over 0.5 µm. With the increase of YIG thickness above 2.5 µm, coupling of SAW to higher order standing spin waves becomes important, which pollutes the spectrum of hybrid magneto-elastic waves, making observation and practical use of nonreciprocal SAW–SSW coupling more difficult.","PeriodicalId":13040,"journal":{"name":"IEEE Magnetics Letters","volume":"16 ","pages":"1-5"},"PeriodicalIF":1.1,"publicationDate":"2025-01-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143553310","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0