Journal of Magnetism and Magnetic Materials最新文献

{"title":"Ferrimagnetic half metals TaMnZ (Z = As, Sb, Bi) for thermoelectric and spintronic applications – Material computations","authors":"Klinton Brito K.,&nbsp;D. Shobana Priyanka,&nbsp;M. Srinivasan,&nbsp;P. Ramasamy","doi":"10.1016/j.jmmm.2024.172564","DOIUrl":"10.1016/j.jmmm.2024.172564","url":null,"abstract":"<div><div>Half metals possess coupling behavior of metals and semiconductors with wide heat transport and spin transport properties. This research article covers the structural, mechanical, electronic, magnetic and thermoelectric properties of the half Heusler alloys TaMnZ (Z = As, Sb, Bi). The equilibrium lattice constants and corresponding ground state energies show that the studied alloys are stable in the ferrimagnetic cubic phase. The band dispersion plots suggest that the compounds TaMnAs, TaMnSb and TaMnBi are half metals with indirect band gap having the band gap energies of 1.13 eV, 1.24 eV and 1.12 eV respectively in the spin down channel. As the materials have 100 % spin polarization with an integer magnetic moment of −1 μ<em>_B</em>_, they are suitable for making spintronic devices such as spin transistors and spin-flip flops. The temperature-dependent thermoelectric properties of the alloys have been studied by classical Boltzmann theory. The materials have low lattice thermal conductivity which was confirmed by Slack’s equation. The obtained thermoelectric figure of merit for p-type TaMnAs, TaMnSb and TaMnBi is 0.7, 0.6 and 0.8 respectively at 1200 K. Similarly, the figure of merit obtained for n-type TaMnAs, TaMnSb and TaMnBi is 0.6, 0.64 and 0.8 respectively at the same temperature. The favourable heat and spin transport properties of these alloys show that they are the potential characters to figure out better thermoelectric and spintronic performance.</div></div>","PeriodicalId":366,"journal":{"name":"Journal of Magnetism and Magnetic Materials","volume":"610 ","pages":"Article 172564"},"PeriodicalIF":2.5,"publicationDate":"2024-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142418993","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":"The energy of 180° domain walls of uniaxial crystals with the different magnetocrystalline anisotropy type","authors":"A.I. Sinkevich,&nbsp;M.B. Lyakhova,&nbsp;E.M. Semenova","doi":"10.1016/j.jmmm.2024.172560","DOIUrl":"10.1016/j.jmmm.2024.172560","url":null,"abstract":"<div><div>The main aim of the present work is to analyze the magnetocrystalline anisotropy (MCA) energy function of uniaxial crystals and to derive analytical expressions for the domain wall (DW) energy taking into account two MCA constants. Thus, the article presents a detailed analysis of the magnetocrystalline anisotropy energy function of uniaxial crystals taking into account two MCA constants (<em>K₁</em>, <em>K₂</em>). The values of the MCA energy extremes and the position of the easy magnetization directions (EMD) and hard magnetization directions (HMD) were determined. The MCA diagram was plotted in “<em>K₁</em>”-“<em>K₂</em>” coordinates. Six types of MCA have been found for uniaxial crystals. Two of them are simple with one maximum and one minimum of the <em>E_A</em>(<em>θ</em>) function, and four are complex with two absolute and one local extreme for each. It is shown that <em>E_A</em>(<em>K₁</em>, <em>K₂</em>) function has the smallest difference between the maximum and minimum values equal to |<em>K₁</em>|/4 and the smallest angle between EMD and HMD equal to π/4 when the <em>K₁</em> + <em>K₂</em> = 0 condition is met. Analytical expressions for the 180° Bloch domain wall energy surface density (γ) were derived for uniaxial crystals with each MCA type. It is found that the γ(<em>K₁</em>, <em>K₂</em>) function has a minimum, equal to <span><math><mrow><mi>γ</mi><mo>=</mo><mn>2</mn><msqrt><mrow><mrow><mi>A</mi><mo>|</mo></mrow><msub><mi>K</mi><mn>1</mn></msub><mrow><mo>|</mo></mrow></mrow></msqrt></mrow></math></span> when the relation <em>K₁</em> + <em>K₂</em> = 0 between MCA constants is satisfied. The derived analytical expressions are useful for a detailed spin-reorientation transition analysis. To illustrate this, examples of the application of the obtained results to MCA analyses of real crystals and DW energy calculations are given.</div></div>","PeriodicalId":366,"journal":{"name":"Journal of Magnetism and Magnetic Materials","volume":"610 ","pages":"Article 172560"},"PeriodicalIF":2.5,"publicationDate":"2024-09-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142419435","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":"Magnetic interaction induced splitting of bands in hexagonal RMnO3 (R = Lu, Y, and Sc) compounds","authors":"D.M.S. Brito,&nbsp;A.F. Lima","doi":"10.1016/j.jmmm.2024.172558","DOIUrl":"10.1016/j.jmmm.2024.172558","url":null,"abstract":"<div><div>In this work, calculations using non-collinear spin density functional theory were performed to study the electronic band structures for different antiferromagnetic orders in hexagonal RMnO₃ (R = Lu, Y, and Sc) compounds. These are an important class of multifunctional materials with interesting properties for various applications. By comparing the band structure of different magnetic configurations, it is observed that some of them exhibit band splitting that can be attributed to ferromagnetic interplane coupling. The energy splitting is significantly larger (331 meV) for the ScMnO₃ compound, which probably has a higher interplane magnetic interaction. In addition, we report that the spin–orbit coupling also induces a splitting of bands in some regions of the Brillouin zone for those magnetic configurations with a weak magnetic moment along the hexagonal c-axis. These findings offer an intriguing insight into the topological characteristics of hexagonal manganites’ band structure, which was previously unexplored in existing literature. This discovery opens avenues for future investigations in this field.</div></div>","PeriodicalId":366,"journal":{"name":"Journal of Magnetism and Magnetic Materials","volume":"610 ","pages":"Article 172558"},"PeriodicalIF":2.5,"publicationDate":"2024-09-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142418996","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":"A low-cost electronic and optical system for magnetic hyperthermia experimental studies","authors":"Yavuz Öztürk ,&nbsp;Ali Altan Yılmaz ,&nbsp;Yiğit Seymen ,&nbsp;Coşkun Harmanşah","doi":"10.1016/j.jmmm.2024.172552","DOIUrl":"10.1016/j.jmmm.2024.172552","url":null,"abstract":"<div><div>Magnetic hyperthermia is an alternative to treatments such as chemotherapy and radiotherapy that employs the heat generated by magnetic nanoparticles under the influence of a magnetic field to kill cancer cells while ideally causing no harm to healthy tissues. A low-cost magnetic hyperthermia investigation platform with commercially available and easy-to-assemble parts was presented to provide and expand research in this area for a larger scientific community. The magnetic hyperthermia measurement system consists of three main parts: a designed thermally insulated sample holder, a commercial 88 kHz magnetic induction heater, and a custom-built fiber optic based refractometer as temperature sensor. The system was tested with commercial EFH-1 magnetic fluids. Time dependent temperature changes were measured for applied magnetic fields of 3.5 kA/m, 4.8 kA/m, and 6.0 kA/m. The corresponding specific loss power values were calculated as 0.28 W/g, 0.51 W/g, and 0.79 W/g, respectively. Intrinsic loss power of commercial ferrofluid was determined as 0.25 ± 0.01 nHm²/kg, found to be comparable to the results of specialized commercial magnetic hyperthermia systems. The results show that the system can easily be used for hyperthermia demonstrations for educational purposes as well as in convenient scientific research with proper calibration.</div></div>","PeriodicalId":366,"journal":{"name":"Journal of Magnetism and Magnetic Materials","volume":"610 ","pages":"Article 172552"},"PeriodicalIF":2.5,"publicationDate":"2024-09-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142419000","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":"Single crystal growth and magnetic properties in triangular chain compound Ni2SiO4","authors":"R. Chen ,&nbsp;Z. Qu ,&nbsp;T. Li ,&nbsp;H.J. Hu ,&nbsp;C.B. Liu ,&nbsp;C. Dong ,&nbsp;Y. Qiu","doi":"10.1016/j.jmmm.2024.172559","DOIUrl":"10.1016/j.jmmm.2024.172559","url":null,"abstract":"<div><div>Sub-centimeter-scale Ni₂SiO₄ single crystals were grown by a flux method with K₂MoO₄ as the flux. The obtained crystals exhibit high quality and were characterized using X-ray diffraction, chemical analysis, and magnetic properties, including high magnetic field (<em>H</em>) magnetization (<em>M</em>) measurements. The results of magnetic susceptibility and specific heat of a single crystal reveal significant magnetic anisotropy and antiferromagnetic ordering below <em>T_N</em> = 30 K. High-field magnetization up to 43 T of polycrystalline shows six magnetic phase transitions at <em>H₁</em> = 14 T, <em>H₂</em> = 18.4 T, <em>H₃</em> = 23 T, <em>H₄</em> = 29 T, <em>H₅</em> = 32.5 T, and <em>H₆</em> = 37 T, forming a complex magnetic phase diagram with seven phases. Notably, the <em>M</em> exhibits a linear relationship with <em>H</em> during phases V (<em>H₄</em> &lt; <em>H</em> &lt; <em>H₅</em>) and VII (<em>H</em> &gt; <em>H₆</em>), showing intercepts at 0 and half of magnetization saturation respectively, implying the presence of a spin flop transition and a 1/2 magnetization plateau. These novel phenomena in such a triangular chain system highlight complex physical nature, making Ni₂SiO₄ a promising candidate for studying intricate magnetic interactions.</div></div>","PeriodicalId":366,"journal":{"name":"Journal of Magnetism and Magnetic Materials","volume":"610 ","pages":"Article 172559"},"PeriodicalIF":2.5,"publicationDate":"2024-09-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142358023","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":"Nonreciprocal damping of spin waves propagating in magnetic domain walls induced by Dzyaloshinskii-Moriya interaction","authors":"Xiang Liu,&nbsp;Zhi-Xiong Li,&nbsp;Xi-Guang Wang,&nbsp;Guang-Hua Guo","doi":"10.1016/j.jmmm.2024.172556","DOIUrl":"10.1016/j.jmmm.2024.172556","url":null,"abstract":"<div><div>The nonreciprocity of spin waves refers to the phenomenon that spin waves propagating in opposite directions display different features. This phenomen becomes a fundamental requirement for implementing magnon logic architectures. The nonreciprocal transportion of spin waves induced by Dzyaloshinskii-Moriya interaction (DMI) has been studied extensively. It is characterized by a shift of spin-wave dispersion. Here we report another feature of the DMI-induced nonreciprocity, i.e., the nonreciprocal spin wave damping. We find that the spin waves propagating with opposite wave vectors in magnetic domain wall have different damping, which is frequency dependent and especially evident in low frequancy range. For spin waves with sufficient low frequencies (around 1 GHz), the damping nonreciprocity is so extreme that spin waves can transport only in one direction, thus realizing the spin-wave diode function. The theoretical predictions are validated by micromagnetic simulations. The findings in this work points out a new feature of DMI-induced spin wave nonreciprocity and may be exploited for designing novel magnonic devices.</div></div>","PeriodicalId":366,"journal":{"name":"Journal of Magnetism and Magnetic Materials","volume":"610 ","pages":"Article 172556"},"PeriodicalIF":2.5,"publicationDate":"2024-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142322153","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":"Robust Multi-Band DNG metamaterial absorber for GPS (L1), ISM, and 5G application with Enhanced polarization and angle stability","authors":"Mayank A. Ardeshana ,&nbsp;Falgunkumar N. Thakkar ,&nbsp;Sunayana G. Domadia","doi":"10.1016/j.jmmm.2024.172554","DOIUrl":"10.1016/j.jmmm.2024.172554","url":null,"abstract":"<div><div>This research introduces a triple-band metamaterial absorber characterized by insensitivity to both polarization and incident angles. The structure includes square ring resonators on the upper side and a continuous metal ground on the lower side, separated by an FR4 substrate. At the lowest operating frequency, the unit cell’s thickness, and length measure 0.0128λ and 0.156λ, respectively. Under normal incidence, the proposed absorber demonstrates three clear absorption peaks at 1.56, 2.43, and 3.36 GHz, achieving absorption rates of 98 %, 99 %, and 97 %, respectively. The absorption response exhibits variation with incident angles up to 70° for both TM and TE polarizations due to its high-level symmetry. This configuration attains negative permittivity and permeability suitable for operational frequencies in the L-band and S-band. The study examines the electric field, impedance, and surface current to provide additional evidence for the absorption analysis. A validated RLC circuit equivalent to the proposed structure has been confirmed using Advanced Design System (ADS). The results indicate a slight deviation, especially at frequencies beyond the resonance frequencies. The structure underwent fabrication and testing in an anechoic chamber, revealing a strong correlation between the simulated and measured results. The suggested absorber holds promise for ISM applications, radar systems, sensing technologies, and energy harvesting systems.</div></div>","PeriodicalId":366,"journal":{"name":"Journal of Magnetism and Magnetic Materials","volume":"610 ","pages":"Article 172554"},"PeriodicalIF":2.5,"publicationDate":"2024-09-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142322149","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":"Influence of Dy3+ doping on Mössbauer, magnetic and microwave absorption properties of M-type Ba0.5Ca0.5DyxFe12-xO19 hexaferrites","authors":"Varsha C. Pujari ,&nbsp;Pramod D. Mhase ,&nbsp;Sunil M. Patange ,&nbsp;P.S. More ,&nbsp;Sher Singh Meena ,&nbsp;Shoyebmohamad F. Shaikh ,&nbsp;Abdullah M. Al-Enizi ,&nbsp;Santosh S. Jadhav","doi":"10.1016/j.jmmm.2024.172555","DOIUrl":"10.1016/j.jmmm.2024.172555","url":null,"abstract":"<div><div>The present research paper reports a systematic study of the magnetic, and structural properties of Ba_0.5Ca_0.5Dy_xFe_12-xO₁₉ M-type hexaferrite. The dysprosium was doped @ x  = 0 − 0.2, keeping Δx = 0.05, in BCDF by the sol–gel self-ignition technique. The sintering of the synthesized samples was performed for 4 h at 1050°C. The crystallographic analysis of the samples was made from the X-ray diffractograms (XRD), while the morphological and elemental analysis was made from field emission scanning electron microscopy (FESEM), and energy-dispersive X-ray spectroscopy (EDAX) profiles. The structural results revealed the formation of the M-type hexaferrite having P6₃/mmc as a space group along with the co-existence of a secondary Fe₂O₃ phase. FESEM micrographs exhibit the hexagonal platelets randomly arranged with agglomerations at some places giving rise to the random variations in particle size with varying ’x’. Magnetic measurements (VSM) show that the saturation magnetization (M_S) and coercivity (H_C) increase with the increasing Dy³⁺ doping pointing towards the fact that the Dy doping in Ba-Ca ferrite can be used to fabricate the hard ferrites with good saturation magnetization. The Mössbauer spectrum recorded at room temperature reveals five superimposed sextets representing the five Fe³⁺ ion sites. Investigating the Microwave absorption (MWA) characteristics in the frequency range 8 − 12 GHz (X-band), reveals that the sample with x  = 0.1 having 3 mm thickness possesses good MWA power. Its minimum RL value for matching frequency 10.06 GHz is approximately −26.96 dB, indicating that more than 90 % of microwaves are absorbed. The current work offers the Dysprosium-doped BCDF hexaferrites, as promising candidates<!--> <!-->for microwave absorption applications.</div></div>","PeriodicalId":366,"journal":{"name":"Journal of Magnetism and Magnetic Materials","volume":"610 ","pages":"Article 172555"},"PeriodicalIF":2.5,"publicationDate":"2024-09-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142326484","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":"Corrigendum to “An induced magnetic field utilization for hybrid nanoliquid flow subject to entropy generation” [J. Magn. Magn. Mater. 576 (2023) 170742]","authors":"T. Hayat ,&nbsp;A. Razaq ,&nbsp;Sohail A. Khan ,&nbsp;A. Alsaedi","doi":"10.1016/j.jmmm.2024.172541","DOIUrl":"10.1016/j.jmmm.2024.172541","url":null,"abstract":"","PeriodicalId":366,"journal":{"name":"Journal of Magnetism and Magnetic Materials","volume":"610 ","pages":"Article 172541"},"PeriodicalIF":2.5,"publicationDate":"2024-09-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142554237","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":"Magnetic injection of α-CP nanoribbons and investigation of spintronic device applications of magnetic α-CP nanoribbons based on first principles calculations","authors":"Yuzhu Wu ,&nbsp;Sheng Liu ,&nbsp;Minyang Zhang ,&nbsp;Ziru Wang ,&nbsp;Sicong Zhu","doi":"10.1016/j.jmmm.2024.172538","DOIUrl":"10.1016/j.jmmm.2024.172538","url":null,"abstract":"<div><div>Since the successful synthesis of α-phosphorus carbide (α-CP) using carbon doping technology, α-CP has exhibited excellent carrier mobility and anisotropy at room temperature, underscoring its potential for spintronic applications. The application of CP in spintronic devices is limited due to its lack of magnetism. Effective magnetic injection in non-magnetic semiconductors can typically be achieved by doping with magnetic atoms. In this study, we calculated the electromagnetic properties of transition metal (TM) atoms adsorbed at different positions on α-CP using first principles. Notably, we found that α-CP nanoribbons adsorbed with Fe and Mn atoms of a specific width exhibit stable half-metallicity. We discovered that α-CP nanoribbons adsorbed with Fe and Mn atoms of a specific width exhibit stable half-metal properties and design magnetic tunnel junctions with half-metallic Fe_H12 and Mn_H12 adsorption structures. The results show that Mn_H12 and Fe_H12 devices exhibit a highly efficient spin filtering effect, with a TMR as high as 5521%. These findings provide theoretical guidance for the application of CP-based spintronic devices.</div></div>","PeriodicalId":366,"journal":{"name":"Journal of Magnetism and Magnetic Materials","volume":"610 ","pages":"Article 172538"},"PeriodicalIF":2.5,"publicationDate":"2024-09-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142311679","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}