Journal of Superconductivity and Novel Magnetism最新文献

{"title":"The Eliashberg Function of Strong Coupling Superconductivity and Lifetime Broadening in Graphene","authors":"Khim S. Hernane,&nbsp;Danilo M. Yanga","doi":"10.1007/s10948-025-06996-7","DOIUrl":"10.1007/s10948-025-06996-7","url":null,"abstract":"<div><p>This paper theoretically investigates the lifetime broadening in graphene using the Eliashberg function of strong coupling superconductivity theory. The normal state lifetime broadening is calculated using the low-temperature limit, while the superconducting-state lifetime broadening is obtained using both low-temperature and low-frequency approximations. In both cases, the Eliashberg function is employed, considering only phonon emissions and electron-phonon interactions on the Fermi surface, with the quasi-elastic approximation term absent in the resulting expression. Notably, the results suggest that this lifetime broadening is highly dependent on the perturbation potential caused by electron-phonon interactions, highlighting the critical role of these interactions in shaping the material’s electronic characteristics. Furthermore, the scattering process dominates the lifetime broadening contribution in the superconducting state, particularly under conditions where phonon-mediated interactions are enhanced. This finding provides valuable insights into the intricate behavior of graphene in superconducting regimes, offering a theoretical framework that advances our understanding of its properties and potential applications.</p></div>","PeriodicalId":669,"journal":{"name":"Journal of Superconductivity and Novel Magnetism","volume":"38 3","pages":""},"PeriodicalIF":1.6,"publicationDate":"2025-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144140120","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":"Spin-Glass Transition in Mn(_{0.75})Co(_{2.25})BO(_{5}) Compound","authors":"D. V. Popov,&nbsp;V. A. Shustov,&nbsp;R. G. Batulin,&nbsp;M. A. Cherosov,&nbsp;E. M. Moshkina,&nbsp;R. M. Eremina","doi":"10.1007/s10948-025-06999-4","DOIUrl":"10.1007/s10948-025-06999-4","url":null,"abstract":"<div><p>Block-shaped crystals of Mn<span>(_{0.75})</span>Co<span>(_{2.25})</span>BO<span>(_{5})</span>, composed of aggregates of small single crystallites, were grown via the flux method using a Bi<span>(_{2})</span>Mo<span>(_{3})</span>O<span>(_{12})</span>-based flux modified with Na<span>(_{2})</span>CO<span>(_{3})</span>. The crystals were powdered prior to analysis. X-ray powder diffraction revealed a <i>Pbam</i> space group with lattice parameters <span>(a = 9.2637(6))</span> Å, <span>(b = 12.3030(5))</span> Å, and <span>(c = 3.0344(1),text{AA })</span>. X-ray diffraction and temperature-dependent measurements of AC and DC magnetization were performed on the Mn<span>(_{0.75})</span>Co<span>(_{2.25})</span>BO<span>(_{5})</span> powder. Measurements of AC and DC magnetization demonstrate a spin-glass transition near 42.5 K.</p></div>","PeriodicalId":669,"journal":{"name":"Journal of Superconductivity and Novel Magnetism","volume":"38 3","pages":""},"PeriodicalIF":1.6,"publicationDate":"2025-05-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144135505","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":"Magnetic Phase Transitions and Hysteresis in Hexagonal Multi-layered Core/Double-Shell Nanowires","authors":"M. Chakir,&nbsp;A. El Ghazrani,&nbsp;L. B. Drissi","doi":"10.1007/s10948-025-06991-y","DOIUrl":"10.1007/s10948-025-06991-y","url":null,"abstract":"<div><p>We investigated the magnetic properties and phase transitions of a hexagonal Ising multi-layered core/double-shell nanowire comprising a spin-5/2 core, a spin-1 inner shell, and a spin-3/2 outer shell. Using Monte Carlo simulations based on the Metropolis algorithm and exact calculations of ground-state phase diagrams, we explored the system’s behavior under various Hamiltonian parameters. The zero-temperature ground-state diagrams (GSDs) revealed multiple stable configurations with diverse topologies, including a compensation phenomenon for negative crystalline fields (<span>(Delta )</span>). The phase diagram in the (T, <span>(Delta )</span>) plane was mapped, identifying ferromagnetic, semi-ordered, and paramagnetic phases. The temperature dependence of total and partial magnetization was analyzed for different values of <span>(Delta )</span>, external field (h), and interface exchange couplings (J<span>( _{int})</span>). Additionally, hysteresis loops were studied under varying nanowire length (L), temperature (T), and J<span>(_{int})</span>, revealing a strong correlation between these parameters and the loops’ shape. This study provides significant insights for the design and optimization of next-generation nanomagnetic systems, with potential applications including, advanced memory storage devices and spintronic components.</p></div>","PeriodicalId":669,"journal":{"name":"Journal of Superconductivity and Novel Magnetism","volume":"38 3","pages":""},"PeriodicalIF":1.6,"publicationDate":"2025-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144108381","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":"Magnetic Ordered State and Enhanced Conductivity in La3-xTbxNi2O7−δ with High Oxygen Pressure Annealing","authors":"Keke Jiao,&nbsp;Rui Niu,&nbsp;Weili Zhen,&nbsp;Huixin Xu,&nbsp;Wanli Zhu,&nbsp;Li Zheng,&nbsp;Yongliang Qin,&nbsp;Changjin Zhang","doi":"10.1007/s10948-025-06989-6","DOIUrl":"10.1007/s10948-025-06989-6","url":null,"abstract":"<div><p>A series of La_3-<i>x</i>Tb_<i>x</i>Ni₂O_7-δ samples have been synthesized for the first time, and the effects of Tb doping in La₃Ni₂O_7-δ are investigated through a comprehensive investigation on the structural parameters, electrical transport, and magnetic properties of the La_3-<i>x</i>Tb_<i>x</i>Ni₂O_7-δ samples. Novel magnetic ordered state has been observed both in the as-prepared La_3-<i>x</i>Tb_<i>x</i>Ni₂O_7-δ compounds and in the samples after high oxygen pressure annealing. The high oxygen pressure annealing results in substantial enhancement of the oxygen content and the increase of nominal valence state of Ni in the La_3-<i>x</i>Tb_<i>x</i>Ni₂O_7-δ samples, leading to an enhanced conductivity. The present work could contribute to the exploration of possible ambient pressure superconductivity in doped La₃Ni₂O_7-δ systems.</p></div>","PeriodicalId":669,"journal":{"name":"Journal of Superconductivity and Novel Magnetism","volume":"38 3","pages":""},"PeriodicalIF":1.6,"publicationDate":"2025-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s10948-025-06989-6.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144117576","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}

{"title":"On the Impact of Magnetic Co-nanoparticles on the Activation Energy and Transport Critical Current Density in Multilayered Y(_{3})Ba(_{5})Cu(_{8})O(_{18-delta }) Superconductors","authors":"Ipsita Mukherjee,&nbsp;Doyel Rakshit,&nbsp;Firoz Molla,&nbsp;Ajay Kumar Ghosh","doi":"10.1007/s10948-025-06990-z","DOIUrl":"10.1007/s10948-025-06990-z","url":null,"abstract":"<div><p>Addition of magnetic nanoparticles of cobalt in the inter-granular region of polycrystalline Y<span>(_{3})</span>Ba<span>(_{5})</span>Cu<span>(_{8})</span>O<span>(_{18-delta })</span> (Y-358) affects both the superfluid phase stiffness (<span>(J)</span> <span>(_{s})</span>) and the transport critical current density (<span>(J)</span> <span>(_{c})</span>). We have studied the current-voltage (<i>IV</i>) characteristics of (i) the pure Y-358 and (ii) Co-mixed Y-358 superconductors. <span>(J_s)</span> via an exponent related to nonlinearity of the <i>IV</i> curves is obtained within the framework of Berezinskii-Kosterlitz-Thouless (BKT) transition. A distinct indication of the BKT transition has been observed in the Y-358+0.75 wt.% Co composite system. <span>(J_c)</span> (<i>T</i>) has also been extracted to understand the effectiveness of Co-nanoparticles. A suppression in the current induced activation energy (<i>U</i>) in zero magnetic field leads to the degradation in transport <span>(J)</span> <span>(_{c})</span> in the composite Y-358 superconductors.</p></div>","PeriodicalId":669,"journal":{"name":"Journal of Superconductivity and Novel Magnetism","volume":"38 3","pages":""},"PeriodicalIF":1.6,"publicationDate":"2025-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144108382","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":"Unveiling the Magneto-Electronic, Mechanical, Thermodynamical, and Optical Behavior of Sc2FeZ (Z = Ga, In, Tl) Heusler Alloy: A DFT-Based Computer Simulation","authors":"Shruti Sharma,&nbsp;Dinesh C. Gupta","doi":"10.1007/s10948-025-06969-w","DOIUrl":"10.1007/s10948-025-06969-w","url":null,"abstract":"<div><p>To discover novel magnetic materials, we discuss computer models for estimating the structural, electrical, and magnetic, mechanical, thermodynamical, and optical characteristics of recently developed Sc₂FeZ (Z = Ga, In, Tl) Heusler compounds. Together with providing the equilibrium values, the cohesive energy curve predicts the strong stability of a specific collection of materials in the F- 43 m phase. Compared to the generalized gradient approximation, the modified Becke-Johnson evaluates the exchange–correlation outcomes more effectively. The compounds in the stable F- 43 m phase have lattice values of 6.41 Å for Sc₂FeGa, 6.67 Å for Sc₂FeIn, and 6.71 Å for Sc₂FeTl, respectively. Half-metallic character is computed from spin magnetic moments derived from band structure and density of states. These compound Sc₂FeZ (Z = Ga, In, Tl) have indirect band gaps in majority spin alignment of 0.52, 0.50, and 0.49, respectively, according to the electronic band structure analysis. By applying the quasi-harmonic approximation of various parameters, such as the Debye temperature, Gruneisen parameters, and specific heat, it is possible to successfully study and clarify the thermodynamical stability of these materials against pressure and temperature. Additionally, the materials show remarkable absorption coefficients in the visible and ultraviolet regions of the light spectrum, suggesting that they are suitable for use in the application of optical and photovoltaic technology. The aforementioned computed properties support the usage of the alloys under study in optoelectronic and green energy applications.</p></div>","PeriodicalId":669,"journal":{"name":"Journal of Superconductivity and Novel Magnetism","volume":"38 3","pages":""},"PeriodicalIF":1.6,"publicationDate":"2025-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144108383","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":"Influence of Calcination Temperature on Magnetic Properties and Antibacterial Activities of Co–Ni-Cd-Fe2O4 Nanocomposites","authors":"Hanaa Sh. Ahmed,&nbsp;Salah R. Saeed,&nbsp;Ali M. Mohammad","doi":"10.1007/s10948-025-06988-7","DOIUrl":"10.1007/s10948-025-06988-7","url":null,"abstract":"<div><p>Developing effective antibacterial agents has become an important challenge, especially with the increasing prevalence of antibiotic-resistant bacteria. Spinel ferrite nanocomposites have attracted considerable interest in biomedical applications due to their magnetic properties and antibacterial potential. The study investigates the effects of calcination temperatures (350, 450, and 550 °C) on the magnetic and antibacterial properties of Co_0.6Ni_0.2Cd_0.2Fe₂O₄ spinel nanocomposites synthesized using the sol–gel method. Understanding this relationship will provide valuable insights into optimizing ferrite-based nanomaterials for medical applications, particularly as antibacterial agents. The resulting nanocomposite was characterized using various techniques. X-ray diffraction study verified the existence of a pristine spinel phase in the specified spacing group of <span>(Fdoverline{3 }m)</span>. In addition, the crystal size slowly grew from 36.74 nm to 41.29 nm as the calcination temperature rose from 350 °C to 550 °C, but the average strain values went down from 1.79 to 1.56. The field emission-scanning electron microscopy analysis showed that the average particle size of Co_0.6Ni_0.2Cd_0.2Fe₂O₄ ferrite was 39.83, 40.96, and 41.60 nm at different calcination temperatures. The energy-dispersive X-ray spectroscopy has also confirmed the presence of Co, Ni, Cd, Fe, and O in all samples. Fourier transform infrared spectroscopy revealed the fingerprint bands υ₁ (~ 578) and υ₂ (~ 381) at 550 °C. Vibrating sample magnetometer analysis revealed that saturation magnetization increases from 53.95 to 57.37 emu/g¹ at 350 and 550 °C, respectively. The antibacterial examination performed via the agar well diffusion technique demonstrated that the Gram-positive bacteria, such as <i>Staphylococcus aureus</i> and <i>Streptococcus mutans</i>, were the most sensitive strains. They exhibited significant susceptibility at the highest concentration of 500 µg/mL (± 25 mm and ± 24 mm). In contrast, Gram-negative bacteria, including <i>Acinetobacter baumannii</i> and <i>Escherichia coli</i>, showed slightly less sensitivity (± 16.2 mm and ± 15 mm). Overall, the synthesized Co_0.6Ni_0.2Cd_0.2Fe₂O₄ spinel nanocomposite demonstrated potent antibacterial activity and can be considered a promising material for biomedical applications.</p><h3>Graphical Abstract</h3>\u0000<div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":669,"journal":{"name":"Journal of Superconductivity and Novel Magnetism","volume":"38 3","pages":""},"PeriodicalIF":1.6,"publicationDate":"2025-05-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144100297","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":"Synthesis and Applications of Magnetic Zeolites: A Comprehensive Review","authors":"Deqi Tang,&nbsp;Manas Pal,&nbsp;Tao Meng,&nbsp;Dongsen Mao,&nbsp;Zhaoteng Xue","doi":"10.1007/s10948-025-06986-9","DOIUrl":"10.1007/s10948-025-06986-9","url":null,"abstract":"<div><p>Magnetic zeolites are gaining a lot of attention for their potential in adsorption and catalytic applications. This review summarizes the structural characteristics and synthesis methods of three types of magnetic zeolites: internal magnetic zeolites, external magnetic zeolites, and complex magnetic zeolites. The application properties of various magnetic zeolites are discussed in detail, including their use in heavy metal adsorption, ammonia nitrogen removal from wastewater, radioactive waste adsorption, and oil contamination removal. Numerous studies have demonstrated that magnetic zeolites possess high magnetization (e.g., &gt; 4 emu·g⁻¹), enabling rapid and efficient magnetic separation of zeolite adsorbents. Magnetic zeolites also exhibit excellent adsorption and catalytic performance, maintaining their effectiveness even after multiple cycles (e.g., more than five cycles).</p></div>","PeriodicalId":669,"journal":{"name":"Journal of Superconductivity and Novel Magnetism","volume":"38 3","pages":""},"PeriodicalIF":1.6,"publicationDate":"2025-05-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144084811","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 the structural, magnetic, and magnetocaloric properties in the La₀.₆Ca₀.₂Sr₀.₂MnO₃ compound","authors":"R. Fakraoui,&nbsp;N. Assoudi,&nbsp;H. Felhi,&nbsp;A. Ben Abderrazak Hajji,&nbsp;R. Dhahri,&nbsp;E. Dhahri","doi":"10.1007/s10948-025-06982-z","DOIUrl":"10.1007/s10948-025-06982-z","url":null,"abstract":"<div><p>In this study, we investigated the structural, magnetic, and magnetocaloric properties, the blocking temperature (TB), and exchange bias (EB) behaviour of a La₀.₆Ca₀.₂Sr₀.₂MnO₃ (LCSMO) compound prepared by solid-state reaction. X-ray diffraction analysis, using Rietveld refinement, showed that the sample crystallize in an orthorhombic structure with the Pbnm space group. Scanning electron microscopy (SEM) confirmed the formation of a single-phase material with an excellent distribution map and the average particle size of <span>(37.8723 pm 0.5536)</span> nm. The M-T curve revealed second-order magnetic phase transitions at the Curie temperature (<i>T</i>_C = 340 K), shifting from a paramagnetic (PM) to ferromagnetic (FM) state. Our results reveal significant magnetic entropy changes, indicating a substantial magnetocaloric effect. Notably, the magnetic entropy change reaches a peak value of 5.763 J/kg.K accompanied by a considerable relative cooling capacity of 335 J/kg, observed under a magnetic field change of 5 T. Hysteresis measurements indicate the presence of a double coercive field leading to an exchange bias (EB) effect in the La₀.₆Ca₀.₂Sr₀.₂MnO₃ manganite compound. The coercivity went from 296.46 Oe (23.6 kA.m⁻¹) at 5 K to 96.23 Oe (7.65 kA.m⁻¹) at ambient temperature indicating soft ferromagnetic behaviour of the studied sample; thus, it is suitable for the production of electromagnetic devices and ultra-high recording devices. To understand the nature and mechanisms behind the phase transition from paramagnetic (PM) to ferromagnetic (FM) states, an analysis of critical exponents was performed. The critical exponents derived from the modified Arrott plots (<span>(beta =0.36615pm 0.0048)</span>) and (<span>(gamma =1.32846pm 0.02092)</span>) closely align with the prediction of the 3D-Heisenberg model.</p></div>","PeriodicalId":669,"journal":{"name":"Journal of Superconductivity and Novel Magnetism","volume":"38 3","pages":""},"PeriodicalIF":1.6,"publicationDate":"2025-05-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144073789","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":"Exploring Monolayer TaF(_4) as a 5(d^1) Analog to Cuprates with Potential for High-T(_c) Superconductivity","authors":"Yang Yang,&nbsp;Shi-Quan Feng,&nbsp;De-Wei Liu,&nbsp;Hai-Yang Dai","doi":"10.1007/s10948-025-06984-x","DOIUrl":"10.1007/s10948-025-06984-x","url":null,"abstract":"<div><p>The quest for cuprate-like materials has gained momentum from recent research on infinite-layer nickelates. TaF<span>(_4)</span>, with its structure of tantalum-centered fluorine octahedra, could potentially function as a <span>(5d^1)</span> analog to cuprates. According to density functional theory (DFT), monolayer TaF<span>(_4)</span> approximates a <span>(d^{1})</span> state, with the <span>(5d_{xy})</span> orbital of Ta almost half-filled. The Fermi level is intersected with a band derived from the <span>(5d_{xy})</span> orbital, resulting in a square-shaped Fermi surface. Energetically, the checkerboard AFM configuration is most favorable, leading to an AFM insulating state upon inclusion of Coulomb interaction. The RPA calculations show that spin susceptibility has notable <span>((pi ,pi ))</span> peaks, and the <span>(d_{x^2-y^2})</span>-wave pairing exhibits the highest eigenvalue compared to other pairing types. The structural and electronic parallels between TaF<span>(_4)</span> and cuprates highlight its potential for high-T<span>(_c)</span> superconductivity, although definitive evidence will require further theoretical and experimental validation.</p></div>","PeriodicalId":669,"journal":{"name":"Journal of Superconductivity and Novel Magnetism","volume":"38 3","pages":""},"PeriodicalIF":1.6,"publicationDate":"2025-05-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143944240","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}