{"title":"Theoretical Study of the Critical Behavior and Magnetocaloric Effect in Rare-Earth Perovskite EuTiO3","authors":"Wanchun Li, Zhengqin Liu, Dong Xie, Xiwei Yao, Zheng Wang, Zexiang Deng","doi":"10.1007/s10948-024-06824-4","DOIUrl":"10.1007/s10948-024-06824-4","url":null,"abstract":"<div><p>The critical behavior and the magnetocaloric effect have been researched in rare-earth perovskite EuTiO<span>(_{varvec{3}})</span>. Using classical Monte Carlo method, we simulate the phase transition behavior of EuTiO<span>(_{varvec{3}})</span> on the Heisenberg model with uniaxial anisotropy and obtain the phase transition temperature <span>(varvec{T}_{varvec{n}} varvec{=5.4})</span> K, which is almost consistent with the experimental results. The entropy change under isothermal <span>(varvec{Delta S})</span> and temperature change under adiabatic <span>(varvec{Delta } {varvec{T}_{varvec{ad}}})</span> are calculated for different external magnetic fields. The results of the relative cooling power (RCP) are linear with the magnetic field. The critical exponents <span>(varvec{beta })</span>=0.269, <span>(varvec{gamma })</span>=1.250, and <span>(varvec{delta })</span>=5.602 are obtained by the power laws. These results are almost identical to those calculated using the MCE scaling law.</p></div>","PeriodicalId":669,"journal":{"name":"Journal of Superconductivity and Novel Magnetism","volume":"37 8-10","pages":"1495 - 1500"},"PeriodicalIF":1.6,"publicationDate":"2024-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142224126","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}
{"title":"Study of Gd/Co Multilayers with Different Cobalt Layer Thickness Values","authors":"Smritiparna Ghosh, Rakhul Raj, Manik Kuila, Zainab Hussain, Dileep Kumar, Mukul Gupta, V.Raghavendra Reddy","doi":"10.1007/s10948-024-06823-5","DOIUrl":"10.1007/s10948-024-06823-5","url":null,"abstract":"<div><p>The present work reports the magnetic and structural behavior of [Gd/Co]<sub>10</sub> multilayers with different Co thickness values, prepared by magnetron sputtering, as a function of thermal annealing. Intermixing is observed with thermal annealing for all the samples; however, complete intermixing is not observed even after annealing at 773 K. Antiparallel alignment of Gd and Co layer magnetization is observed for pristine samples from room temperature X-ray magnetic circular dichroism measurements. Magnetic compensation temperature is found to vary depending on the thickness of Co layers. Temperature-dependent magneto-optical Kerr effect (MOKE) measurements depict the inversion of loops across magnetic compensation temperature for all the pristine samples. However, no signatures of magnetic compensation are observed in the low-temperature MOKE loops for the annealed samples. MOKE loops of the annealed samples exhibit double hysteresis loops. The results are explained in terms of intermixing with annealing.</p></div>","PeriodicalId":669,"journal":{"name":"Journal of Superconductivity and Novel Magnetism","volume":"37 8-10","pages":"1755 - 1762"},"PeriodicalIF":1.6,"publicationDate":"2024-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142224129","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}
{"title":"Lepidagathis ananthapuramensis Leaf Extract Stabilized Co3O4 Nanoparticles and its Structural, Optical and Magnetic Properties","authors":"K. K. Supin, M. Vasundhara","doi":"10.1007/s10948-024-06817-3","DOIUrl":"10.1007/s10948-024-06817-3","url":null,"abstract":"<div><p>The present work focusses on the green synthesis of Co<sub>3</sub>O<sub>4</sub> nanoparticles (NPs) using <i>Lepidagathis ananthapuramensis</i> leaf extract and to investigate its structural, optical, morphological and magnetic properties. The structural information confirmed the formation of spinel type polycrystalline cubic symmetry with space group Fd-3 m. The Fourier transform infrared spectroscopic studies revealed the sharp doublet peak in the finger print region pertaining to the Co<sup>2+</sup> and Co<sup>3+</sup> ions. The X-ray photoelectron spectroscopy further confirmed the presence of Co<sup>3+</sup> and Co<sup>2+</sup> ions in which Co<sup>3+</sup> ions are present more than Co<sup>2+</sup> ions. The UV–Visible spectroscopic studies indicate that there are two characteristic absorptions of Co<sub>3</sub>O<sub>4</sub> NPs indicating the ligand to metal charge transfer. The morphological analysis of Co<sub>3</sub>O<sub>4</sub> NPs using field emission scanning microscope and high-resolution transmission electron microscopy, showed irregular shapes of different sizes with Co mostly at surface than the core. The magnetic data revealed the existence of antiferromagnetic nature co-hosting weak ferromagnetism. The detailed explanations of a straightforward and affordable method for creating spinel type Co<sub>3</sub>O<sub>4</sub> and their structural and magnetic properties were explained.</p></div>","PeriodicalId":669,"journal":{"name":"Journal of Superconductivity and Novel Magnetism","volume":"37 8-10","pages":"1743 - 1753"},"PeriodicalIF":1.6,"publicationDate":"2024-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142227649","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}
{"title":"The Origin of the Dirac Linear Spectrum and a Study on the Topological Bilayers","authors":"Mauro M. Doria, Edinardo I. B. Rodrigues","doi":"10.1007/s10948-024-06819-1","DOIUrl":"10.1007/s10948-024-06819-1","url":null,"abstract":"<div><p>We propose that the linear Dirac spectrum and the Rashba interaction, two important features of the topological insulators, have a common origin rooted on the well-known non-relativistic Schrödinger kinetic energy for fermions subject to the spin-momentum locking condition described here. This approach yields that the quasi-particles with linear Dirac spectrum are skyrmions, namely, three-dimensional vortices with topological charges surrounded by a residual local magnetic field. Within this framework, the spectrum of topological bilayers is obtained and shown for a small wave number to have two branches, one quadratic and the other linear but with twice the velocity of the single layer case.</p></div>","PeriodicalId":669,"journal":{"name":"Journal of Superconductivity and Novel Magnetism","volume":"37 11-12","pages":"1983 - 1989"},"PeriodicalIF":1.6,"publicationDate":"2024-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142185022","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}
Barbara Montañes, Pábel Machado, Ernesto Medina, Ismardo Bonalde
{"title":"Spin Susceptibility of Helical Carbon-Based Nanostructures with Almost Filled Band and Spin-Orbit Coupling","authors":"Barbara Montañes, Pábel Machado, Ernesto Medina, Ismardo Bonalde","doi":"10.1007/s10948-024-06820-8","DOIUrl":"10.1007/s10948-024-06820-8","url":null,"abstract":"<div><p>Some theoretical studies using perturbation and tight-binding methods have tried to shed light on the magnetic behaviors of carbon-based nanostructures in the limit of wave vector <span>(mathbf {q=0})</span>. In a recent work, we studied a half-filled model of helical carbon chains to gain new insights for <span>(mathbf {q ne 0})</span>. Although in carbon the energy bands are usually derived from partially filled atomic <i>p</i>-shells, here we explore the hole contribution to these magnetic responses. We calculate the longitudinal spin susceptibility of an almost-filled tight-binding model of a helical chain for <span>(mathbf {qne 0})</span>. We find that when the Fermi level lies at the band edges, the system shows for positive chirality a divergent paramagnetic susceptibility. This result is in agreement with that previously reported for the macroscopic limit <span>(mathbf {q=0})</span>.</p></div>","PeriodicalId":669,"journal":{"name":"Journal of Superconductivity and Novel Magnetism","volume":"37 11-12","pages":"1977 - 1982"},"PeriodicalIF":1.6,"publicationDate":"2024-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142185023","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}
{"title":"Tuning the Magnetoimpedance, Magnetoresistance, and Magnetoinductance of Melt-Spun Ribbons","authors":"M. Inchara, D. Arvindha Babu, Ganesh Kotagiri","doi":"10.1007/s10948-024-06818-2","DOIUrl":"10.1007/s10948-024-06818-2","url":null,"abstract":"<div><p>Magnetoresistance (MR), magnetoinductance (mi), and magnetoimpedance (MI) studies on the as-quenched and annealed Fe<sub>72</sub>Si<sub>10</sub>Cu<sub>1</sub>Nb<sub>2</sub>B<sub>15</sub>, Co<sub>72</sub>Ni<sub>5</sub>Si<sub>5</sub>Cu<sub>1</sub>Nb<sub>2</sub>B<sub>15</sub>, and Co<sub>77</sub>Si<sub>5</sub>Cu<sub>1</sub>Nb<sub>2</sub>B<sub>15</sub> ribbons have been carried out in the present investigation. Structural studies indicate that all as-quenched samples are in the amorphous phase. The asymmetry in the MI, MR, and mi curves is noticed and is attributed to induced magnetocrystalline anisotropy and hysteretic magnetization. Among all three samples, the Co<sub>77</sub>Si<sub>5</sub>Cu<sub>1</sub>Nb<sub>2</sub>B<sub>15</sub> ribbons exhibit the highest magnetization and MI values. The development of a strong transverse magnetic anisotropy upon annealing has been observed in the Co<sub>77</sub>Si<sub>5</sub>Cu<sub>1</sub>Nb<sub>2</sub>B<sub>15</sub> ribbons, while such features are not observed in other cases. The present study shows that 5% Ni substitution in Co<sub>77</sub>Si<sub>5</sub>Cu<sub>1</sub>Nb<sub>2</sub>B<sub>15</sub> samples significantly reduces the transverse anisotropy, indicating that the transverse anisotropy can be tuned through Ni substitution.</p></div>","PeriodicalId":669,"journal":{"name":"Journal of Superconductivity and Novel Magnetism","volume":"37 8-10","pages":"1733 - 1742"},"PeriodicalIF":1.6,"publicationDate":"2024-08-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142224127","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}
{"title":"Investigation of Strong Tailored Magnetocaloric Effect in Ba(Fe1-xScx)12O19","authors":"Mahmoud A. Hamad, Hatem R. Alamri","doi":"10.1007/s10948-024-06815-5","DOIUrl":"10.1007/s10948-024-06815-5","url":null,"abstract":"<div><p>By simulating the thermomagnetization of Ba(Fe<sub>1-<i>x</i></sub>Sc<sub><i>x</i></sub>)<sub>12</sub>O<sub>19</sub> from approximately 100 to 750 K, the magnetocaloric effect (MCE) in Ba(Fe<sub>1-<i>x</i></sub>Sc<sub><i>x</i></sub>)<sub>12</sub>O<sub>19</sub> samples is approximated. Intriguingly, the thermomagnetic property of the undoped sample BaFe<sub>12</sub>O<sub>19</sub> is described as a conventional MCE for high temperatures. However, at doping levels <i>x</i> of 0.128, 0.153, and 0.189, respectively, the thermomagnetic property of Sc-doped samples is defined as an inverse MCE below temperatures of 163, 239, and 318 K. In contrast, thermomagnetic property of Ba(Fe<sub>1-<i>x</i></sub>Sc<sub><i>x</i></sub>)<sub>12</sub>O<sub>19</sub> is described as conventional MCE above those temperatures. Additionally, Sc doping makes it possible for MCE in Ba(Fe<sub>1-<i>x</i></sub>Sc<sub><i>x</i></sub>)<sub>12</sub>O<sub>19</sub> to be strongly tailored. This is helpful for operating a magnetic refrigerator (MR) which occurs in various temperature ranges and results in a higher working temperature range. A promising function for Ba(Fe<sub>1-<i>x</i></sub>Sc<sub><i>x</i></sub>)<sub>12</sub>O<sub>19</sub> samples in MR at high-temperature applications in the automotive and food industries or aerospace.</p></div>","PeriodicalId":669,"journal":{"name":"Journal of Superconductivity and Novel Magnetism","volume":"37 8-10","pages":"1563 - 1567"},"PeriodicalIF":1.6,"publicationDate":"2024-08-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142185024","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}
P. Saraswathi, S. Madeswaran, S. Subhavenkadesh, R. Ezhil Vizhi, D. Rajan Babu
{"title":"Enhancement of Coercivity in α-Mn(Al) Magnetic Nanopowders Processed by High-Energy Ball Milling","authors":"P. Saraswathi, S. Madeswaran, S. Subhavenkadesh, R. Ezhil Vizhi, D. Rajan Babu","doi":"10.1007/s10948-024-06816-4","DOIUrl":"10.1007/s10948-024-06816-4","url":null,"abstract":"<p>We report the achievement of a high coercivity (Hc) value of 3 kOe for Mn<sub>54</sub>Al<sub>46</sub> powders produced by high-energy ball milling without any heat treatment. The ferromagnetic α-Mn(Al) alloy powders were prepared with Mn (54 at%) and Al (46 at%) as the constituent metal elements. Analysis and discussion were held regarding the potential causes of the observed enhancement in the magnetic properties of the ball-milled powders in relation to their phase composition and microstructure. The process of milling causes partial solubilisation of Al atoms in the α-Mn phase and a change in the powder magnetic characteristics from paramagnetic to ferromagnetic. The existence of γ<sub>2</sub> and β phases was identified by XRD after long hours of the milling process. In addition, it was found that a longer milling time resulted in a smaller crystallite size, which also resulted in a decrease in magnetic saturation (Ms) but an increase in coercivity (H<sub>C</sub>). Without applying any extra heat treatment, the Mn-Al powders milled for 6 h had optimum magnetic properties: Hc = 3.0 kOe, Mr = 0.05 emu/g, Ms = 0.19 emu/g, and (BH)max = 432 J/m<sup>3</sup>.</p>","PeriodicalId":669,"journal":{"name":"Journal of Superconductivity and Novel Magnetism","volume":"37 8-10","pages":"1723 - 1731"},"PeriodicalIF":1.6,"publicationDate":"2024-08-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142185025","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}
{"title":"Bethe’s Wave-Function Revisited","authors":"Jacob Szeftel, Jean-Claude Lévy","doi":"10.1007/s10948-024-06814-6","DOIUrl":"10.1007/s10948-024-06814-6","url":null,"abstract":"<div><p>The <i>scattering</i> eigenstates of <i>any</i> Hamiltonian of electrons, coupled through a two-body force and moving on a one-dimensional lattice, are shown to be Bethe’s wave-functions. The energy of the groundstate is compared with values, obtained previously for the Hubbard Hamiltonian thanks to another Bethe’s wave-function-based procedure and within the framework of the correlated Fermi gas. The same analysis is applied to electrons, interacting on neighbouring sites. The significance of those various groundstates is assessed with help of thermodynamics.</p></div>","PeriodicalId":669,"journal":{"name":"Journal of Superconductivity and Novel Magnetism","volume":"37 8-10","pages":"1371 - 1379"},"PeriodicalIF":1.6,"publicationDate":"2024-08-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142227650","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}
Shivakumar Venkataramaiah, Manjula M. Venkatappa, Chikkappa Udagani, Devaraja Sannaningaiah
{"title":"Green-Synthesized Cobalt Ferrite Nanoparticle Alleviated Sodium Nitrite-Induced Oxidative Stress Through Its Anti-oxidant Property and Displayed Anti-inflammatory, Anti-diabetic and Anti-platelet Activities","authors":"Shivakumar Venkataramaiah, Manjula M. Venkatappa, Chikkappa Udagani, Devaraja Sannaningaiah","doi":"10.1007/s10948-024-06813-7","DOIUrl":"10.1007/s10948-024-06813-7","url":null,"abstract":"<div><p>The present study unveils the <i>Decalepis hamiltonii</i> leaves extract mediated biosynthesis of cobalt ferrite nanoparticles (<i>DHLE.CoFe</i><sub><i>2</i></sub><i>O</i><sub><i>4</i></sub> NPs) and its role on oxidative stress-induced inflammation, thrombosis and diabetes. <i>DHLE.CoFe</i><sub><i>2</i></sub><i>O</i><sub><i>4</i></sub> NPs were characterized using various techniques such as <i>PXRD</i>, <i>FTIR</i>, <i>SEM</i>, <i>EDAX</i>, <i>HR-TEM</i> and <i>VSM</i>. <i>DHLE.CoFe</i><sub><i>2</i></sub><i>O</i><sub><i>4</i></sub> NPs revealed irregular polygonal shapes with uneven distribution of particles with an average size of 19.13 nm. The <i>DHLE.CoFe</i><sub><i>2</i></sub><i>O</i><sub><i>4</i></sub> NPs displayed considerable anti-oxidant activity by scavenging DPPH free radical about 60.35% at 150 µg/mL concentration with an IC<sub>50</sub> value of 54.18 µg/mL. Similarly, <i>DHLE.CoFe</i><sub><i>2</i></sub><i>O</i><sub><i>4</i></sub> NPs reduced 744.06 µM ferric ions at the concentration of 150 µg/mL with an IC<sub>50</sub> value of 44.08 µg/mL. <i>DHLE.CoFe</i><sub><i>2</i></sub><i>O</i><sub><i>4</i></sub> NPs were non-toxic to RBCs and exhibited anti-oxidant property by regulating the stress markers such as <i>LPO</i>, <i>PCC</i>, <i>TT</i>, and anti-oxidant enzymes like <i>CAT</i> and <i>SOD</i> activities in NaNO<sub>2</sub>-induced oxidative stress in RBCs model. Furthermore, <i>DHLE.CoFe</i><sub><i>2</i></sub><i>O</i><sub><i>4</i></sub> NPs were found to protect the RBCs’ membrane by inhibiting the hypo-tonicity and heat-induced hemolysis suggesting its anti-hemolytic activity. Furthermore, <i>DHLE.CoFe</i><sub><i>2</i></sub><i>O</i><sub><i>4</i></sub> NPs exhibited fair anti-inflammatory property that was tested using egg albumin, BSA denaturation and proteinase inhibition assays. In addition, <i>DHLE.CoFe</i><sub><i>2</i></sub><i>O</i><sub><i>4</i></sub> NPs inhibited α-amylase (46.45%) and α-glucosidase (48.66%) activity respectively and revealed its anti-diabetic property. Most importantly, <i>DHLE.CoFe</i><sub><i>2</i></sub><i>O</i><sub><i>4</i></sub> NPs showed anti-platelet activity by inhibiting both ADP and epinephrine-induced platelet aggregation with an inhibition percentage of 58.73 and 63.88, respectively. In conclusion, <i>DHLE.CoFe</i><sub><i>2</i></sub><i>O</i><sub><i>4</i></sub> NPs appear to be a good candidate in regulating oxidative stress-induced, inflammation, haemolysis, diabetes and thrombosis.</p></div>","PeriodicalId":669,"journal":{"name":"Journal of Superconductivity and Novel Magnetism","volume":"37 11-12","pages":"1839 - 1857"},"PeriodicalIF":1.6,"publicationDate":"2024-08-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142224128","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}