Anshu Gaur, Saarthak Dulgaj, Biswaranjan Sahu, S. Srinath
{"title":"Structural, Magnetic, and Dielectric Properties of SrFe12O19-Ba0.85Ca0.15Ti0.9Zr0.1O3 Composites","authors":"Anshu Gaur, Saarthak Dulgaj, Biswaranjan Sahu, S. Srinath","doi":"10.1007/s10948-024-06778-7","DOIUrl":"10.1007/s10948-024-06778-7","url":null,"abstract":"<div><p>Structural, magnetic, and dielectric properties of <span>(x)</span>SrFe<sub>12</sub>O<sub>19</sub>-(1-<span>(x)</span>)Ba<sub>0.85</sub>Ca<sub>0.15</sub>Ti<sub>0.9</sub>Zr<sub>0.1</sub>O<sub>3</sub> multiferroic composite prepared by sintering the composite mixture of sol-gel synthesized SrFe<sub>12</sub>O<sub>19</sub> (SrF) and Ba<sub>0.85</sub>Ca<sub>0.15</sub>Ti<sub>0.9</sub>Zr<sub>0.1</sub>O<sub>3</sub> (BCTZ) are reported. Structural parameters (lattice parameter, bond length, and lattice strain) of parent phases in their pure and composite forms are correlated to indicate the lattice interaction between the two phases. The magnetic moment per gram of SrF (<span>({M}_{SrF})</span>) in the composite is higher than that in the SrF, related to the changes in the Fe-O-Fe bond angles. The room temperature dielectric response of the composites in the 100 Hz–10 MHz frequency range is modeled by the Cole–Cole relaxation and Jonscher power law equations to mark the different contributions (ferroelectric dipoles, charge carriers).</p></div>","PeriodicalId":669,"journal":{"name":"Journal of Superconductivity and Novel Magnetism","volume":"37 5-7","pages":"1285 - 1291"},"PeriodicalIF":1.6,"publicationDate":"2024-06-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141547949","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}
Somnath Das, Jacob Debbarma, Avijit Mondal, Premkumar Murugaiyan, Rajat K. Roy, Ashis K. Panda
{"title":"Evaluation of Shot Peened SS 347 Tubes Through a Magnetostrictive Sensing (MsS) Device","authors":"Somnath Das, Jacob Debbarma, Avijit Mondal, Premkumar Murugaiyan, Rajat K. Roy, Ashis K. Panda","doi":"10.1007/s10948-024-06784-9","DOIUrl":"10.1007/s10948-024-06784-9","url":null,"abstract":"<div><p>Impact of shot peening on SS347 tube has been investigated using MagStrics, a magnetostrictive sensing (MsS) device comprising of rapidly quenched ribbon as sensor element. Two tubes of SS347 have been considered in pre- and post-shot peened state. Annealed ribbon as sensor element showed enhanced MsS signal. Using the annealed ribbon as sensor element, the MsS signal amplitude in shot peened tube was found to be distinctly different from un-peened sample. This was associated to magnetic phase evolutions in the pipe internal surface due to shot peening. Such phenomena have been endorsed through SEM–EDX compositional analysis and correlated through simulations using COMSOL Multiphysics.</p></div>","PeriodicalId":669,"journal":{"name":"Journal of Superconductivity and Novel Magnetism","volume":"37 5-7","pages":"1293 - 1298"},"PeriodicalIF":1.6,"publicationDate":"2024-06-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141514904","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}
Leila Alicheraghi, Ali Ghasemi, Ebrahim Paimozd, Mohammad Reza Nasr-Esfahani
{"title":"Insight into the Intra and Inter-wire Magnetic Interactions of Co Nanowire Arrays by FORC Diagrams","authors":"Leila Alicheraghi, Ali Ghasemi, Ebrahim Paimozd, Mohammad Reza Nasr-Esfahani","doi":"10.1007/s10948-024-06736-3","DOIUrl":"https://doi.org/10.1007/s10948-024-06736-3","url":null,"abstract":"<p>Understanding and controlling the magnetic behavior of nanowire (NW) arrays is a fundamental step for developing novel future-generation devices. The current research investigated the role of copper pre-plating thickness on the structural and magnetic interactions of cobalt NW arrays. The NWs were grown in the anodic aluminum oxide (AAO) templates with a nanopore diameter of 30 nm by using a pulse electrodeposition (PED). The thickness of Cu pre-plating varied by adjusting the amount of electrodeposition (ED) Coulomb charge to about 0.03–0.7 C. The intensity of the Co-hcp peaks in the X-ray diffraction (XRD) pattern changes with the increase of Cu pre-plating, which can be related to ion mobility and growth kinetics during the ED process. The hysteresis curves indicate that effective magnetic anisotropy fields (<span>({text{H}}_{text{A}}^{text{eff}}))</span> increase from 7200 to 11,000 Oe with increasing Cu thickness. The coercivity of Co nanowire arrays without Cu pre-plating was 1170 Oe and rose to 1870 Oe for optimum Cu thickness with 0.3 C pre-plating. The switching field distribution (SFD) extracted from hysteresis curves agrees well with the squareness ratio. Also, the SFD indicates an exchange coupling between the interfaces of the magnetic phases in the optimum sample. The regions formed in the first-order reversal curve (FORC) diagram showed crystalline features and magnetic phase interactions between the intra and inter-wire. Further, the FORC analysis showed the same crystalline features as those obtained from the XRD structural analysis.</p>","PeriodicalId":669,"journal":{"name":"Journal of Superconductivity and Novel Magnetism","volume":"17 1","pages":""},"PeriodicalIF":1.8,"publicationDate":"2024-06-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141514905","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":"Tunable Magnetic Skyrmion Motion on a Nanostrip Using Current and Spin Waves: A Micromagnetic Study","authors":"Payal Bhattacharjee, Saswati Barman","doi":"10.1007/s10948-024-06769-8","DOIUrl":"10.1007/s10948-024-06769-8","url":null,"abstract":"<div><p>Nowadays, the concept of non-trivial topological protection and the nanoscale size of nanomagnetic particles constitute a major area of research. Due to topological protection stability, nanoscale size, and the requirement of low spin current density for motion, skyrmions have attracted great attention in next-generation spintronic devices as robust information carriers. We study the motion of an isolated magnetic skyrmion with induced interfacial Dzyaloshinskii-Moriya interaction (iDMI) instigated by spin waves and driven by spin current with variation in different parameters in a nanotrack of finite length using micromagnetic simulations. It is found that the magnetic skyrmion moves in the same direction as the direction of propagation of the spin waves. The skyrmion initially experiences an acceleration in its motion; thereafter, the velocity decreases exponentially. The motion of the magnetic skyrmion initiates as the momentum of the spin wave gets transferred to it. The motion of the magnetic skyrmion is found to be significantly dependent on the variation of parameters like frequency and amplitude of the incident spin waves, as well as the damping parameter and the strength of the applied spin-polarized current. The results obtained in this work could become useful to design skyrmion-based spintronic information-carrying and storage devices.</p></div>","PeriodicalId":669,"journal":{"name":"Journal of Superconductivity and Novel Magnetism","volume":"37 8-10","pages":"1519 - 1527"},"PeriodicalIF":1.6,"publicationDate":"2024-06-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141547950","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}
Hasan Mahmud, Jamal Uddin Ahamed, Md. Nazrul Islam Khan
{"title":"Study the Effect of Mn-Substitution on the Structural, Magnetic, and Dielectric Properties of Ba0.75Sr0.25Ti1−xMnxO3 Ceramics","authors":"Hasan Mahmud, Jamal Uddin Ahamed, Md. Nazrul Islam Khan","doi":"10.1007/s10948-024-06774-x","DOIUrl":"10.1007/s10948-024-06774-x","url":null,"abstract":"<div><p>Conventional solid-state reaction method has been cautiously employed to prepare the Ba<sub>0.75</sub>Sr<sub>0.25</sub>Ti<sub>1−<i>x</i></sub>Mn<sub><i>x</i></sub>O<sub>3</sub> ceramic where Sr was firmly doped at the Ba site and Mn was doped with different densities at the Ti site. Since the performance of materials varies with frequency, electric field, and temperature, we have elucidated the various features of the synthesized samples for the sake of scientific benefit in the fields of microelectronics, telecommunications, and spintronics. Structural and morphological features of the ready samples were examined by X-ray diffraction and scanning electron microscopy (SEM). The crystal's tetragonal behavior was verified by XRD analysis, and with the increment of Mn content, the volume of the unit cell is little changed. It is clear from the SEM images that the grain size of the prepared samples increases with Mn doping. The dielectric properties of Ba<sub>0.75</sub>Sr<sub>0.25</sub>Ti<sub>1−<i>x</i></sub>Mn<sub><i>x</i></sub>O<sub>3</sub> were measured by dielectric constant and AC conductivity in a wide range of frequency from 1 kHz to 10 MHz. This result also explores that the dielectric constant rises with the concentration of Mn, most significantly for the 20% Mn substitution with Ti. We also found from the experimental result that the dielectric constant is high in the frequency range of 1–10 kHz. The magnetic permeability of the prepared sample increased with 10% and 20% of Mn replacement. Ferromagnetic features with a weak coercive field and the increased ferromagnetic order with rising Mn concentrations of the prepared samples were confirmed by VSM data analysis. The developed multiferroic materials can be employed in future spintronic devices like spin transistors, sensors, spin diodes, and memory devices.</p></div>","PeriodicalId":669,"journal":{"name":"Journal of Superconductivity and Novel Magnetism","volume":"37 8-10","pages":"1569 - 1584"},"PeriodicalIF":1.6,"publicationDate":"2024-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141514906","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}
K. Sai Maneesh, Himalay Basumatary, C. Vishnu Mohan Rao, Radhika Chada, M. Manivel Raja
{"title":"Structural and Magnetization Studies of Cu Buffered Fe-Ga Films Grown on Si and Si/SiO2 Substrates","authors":"K. Sai Maneesh, Himalay Basumatary, C. Vishnu Mohan Rao, Radhika Chada, M. Manivel Raja","doi":"10.1007/s10948-024-06771-0","DOIUrl":"10.1007/s10948-024-06771-0","url":null,"abstract":"<div><p>In this paper, we report a systematic study on effect of film thickness and substrate temperature on structural and magnetic behaviour of Fe-Ga films with Cu buffer layer, deposited on Si and Si/SiO<sub>2</sub> substrates at room and high substrate temperatures. Grazing incidence X-ray diffraction studies reveal that all the films are crystalline with disordered alpha-Fe phase, which is BCC A2 phase. At 300 °C of substrate temperature, films deposited on Si/SiO<sub>2</sub> substrate found to nucleate L1<sub>2</sub> phase from matrix of A2 phase, which is not seen in Si based films. Irrespective of substrate material, Fe-Ga films found to exist in dual phases at 500 °C substrate temperature. Lattice strains of the films were calculated from X-ray diffraction patterns, using Williamson-Hall method. From X- ray reflectivity analysis of all the films, film density, thickness and roughness of Fe-Ga layer and buffer layer were obtained after fitting the reflectivity data. Presence of an oxide layer is also evident from reflectivity fitting analysis. From magnetization studies it is clear that, all the films exhibited strong in-plane anisotropy. Saturation magnetization of films was found to vary with change in film density and oxide layer thickness of films. Saturation magnetization of films deposited on Si substrates found to decrease with decrease in film density. Coercivity of films found to vary with change in crystallite size, interface roughness and lattice strain of films. Films deposited on Si substrates are sensitive to strain with change in film thickness and films deposited on Si/SiO<sub>2</sub> substrates are sensitive to strain with change in deposition temperature. Coercivity in films found to decrease with decrease in film roughness, increase in crystallite size and lowering the tensile lattice strain.</p></div>","PeriodicalId":669,"journal":{"name":"Journal of Superconductivity and Novel Magnetism","volume":"37 5-7","pages":"1269 - 1283"},"PeriodicalIF":1.6,"publicationDate":"2024-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141514907","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}
Wedad A. Alwesabi, Prajakta D. Dange, Anil V. Raut, Gulab M. Puri, Rahul M. Khobragade, Pravina P. Pawar, S. V. N. Pammi, Challa Kiran Kumar, Pratap Kollu
{"title":"Microstructural, Optical, and Antimicrobial Activity of ZnO-CuO NCP Prepared Using Co-precipitation Technique","authors":"Wedad A. Alwesabi, Prajakta D. Dange, Anil V. Raut, Gulab M. Puri, Rahul M. Khobragade, Pravina P. Pawar, S. V. N. Pammi, Challa Kiran Kumar, Pratap Kollu","doi":"10.1007/s10948-024-06760-3","DOIUrl":"https://doi.org/10.1007/s10948-024-06760-3","url":null,"abstract":"<p>ZnO-CuO nanocomposite particles (NCPs) were synthesized at different molar ratios (4:1, 3:2, and 1:4) through the use of the co-precipitation technique, which produced interesting modifications in the particle’s physical characteristics. XRD showed that average crystallite size (<i>D</i><sub>avg</sub>) decreased noticeably from about 22.07 to 15.98 nm as the concentration of CuO increased within the ZnO matrix. This pattern points to a major impact of CuO content on the composite’s structural properties. Fourier-transform infrared spectroscopy (FTIR), two distinct functional groups were identified: <i>v</i><sub>1</sub> and <i>v</i><sub>2</sub>, which were detected at approximately 524 cm<sup>−1</sup> and 427 cm<sup>−1</sup>, respectively, and were linked to intrinsic and extrinsic vibrations. These spectral characteristics highlight the complex interaction between ZnO and CuO and offer important insights into the chemical bonding and molecular interactions within the composite system. The ZnO-CuO nanocomposite was subjected to field emission scanning electron microscopy and energy-dispersive X-ray analysis (SEM-EDX) which showed spherical shapes with increments in agglomeration. UV-Vis absorption spectra revealed a blue shift with increasing absorption in the UV region. The energy band gap of ZnO in its pristine state was found to be 3.31 eV, but in the ZnO<sub>4</sub>-CuO<sub>1</sub> composition, it increased to 5.48 eV, suggesting that the addition of CuO caused a significant change in the electronic structure. Significantly, ZnO-CuO NCP antimicrobial evaluation demonstrated exceptional antibacterial efficacy against bacterial strains that were both Gram positive and Gram negative, in addition to fungal pathogens. This strong antimicrobial activity highlights the synthetic nanocomposite’s potential use in fighting a range of microbial infections and highlights their bright future in the environmental and biomedical fields.</p>","PeriodicalId":669,"journal":{"name":"Journal of Superconductivity and Novel Magnetism","volume":"28 1","pages":""},"PeriodicalIF":1.8,"publicationDate":"2024-06-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141514908","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":"A Phenomenological Approach for Predicting Magnetic and Magnetocaloric Properties in the (La2MnNiO6)x / (La2MnCoO6)1−x Composite","authors":"Abderrazak Boubekri, Zakaria Elmaddahi, Younes Jarmoumi, Karima Gueddouch, Abdeslam Farchakh, Mohamed EL Hafidi","doi":"10.1007/s10948-024-06777-8","DOIUrl":"10.1007/s10948-024-06777-8","url":null,"abstract":"<div><p>In this paper, we have investigated the magnetic and magnetocaloric characteristics of a La<sub>2</sub>MnNiO<sub>6</sub> composite, in conjunction with La<sub>2</sub>MnCoO<sub>6</sub>. This composite consists of two phases of double perovskite materials. Employing the mean-field approximation, we successfully modeled how magnetization and the change in magnetic entropy vary with temperature under different magnetic fields in our samples. This phenomenological model helped us also plot the maximum magnetic entropy change (-ΔS<sub>M</sub>)<sub>max</sub>, full width at half-maximum δT<sub>FWHM</sub>, and relative cooling power (RCP). Our analysis has revealed an optimal plateau-type magnetocaloric effect near room temperature, corresponding to a specific composition <i>x</i> between 0.2 and 0.5. Ultimately, this theoretical model lets us predict the magnetic and magnetocaloric behavior of composite materials, providing a foundation for future studies.</p></div>","PeriodicalId":669,"journal":{"name":"Journal of Superconductivity and Novel Magnetism","volume":"37 8-10","pages":"1401 - 1410"},"PeriodicalIF":1.6,"publicationDate":"2024-06-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141552706","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}
H. Ouachtouk, A. Harbi, S. Azerblou, A. Azouaoui, M. Moutaabbid, El. Tace
{"title":"Synthesis, Characterization, Magnetic, Elastic, and Electronic Properties of La2ZnMnO6 Double Perovskite","authors":"H. Ouachtouk, A. Harbi, S. Azerblou, A. Azouaoui, M. Moutaabbid, El. Tace","doi":"10.1007/s10948-024-06776-9","DOIUrl":"10.1007/s10948-024-06776-9","url":null,"abstract":"<div><p>The perovskite La<sub>2</sub>ZnMnO<sub>6</sub> was successfully synthesised using the conventional solid-state reaction. X-ray diffraction shows that the perovskite La<sub>2</sub>ZnMnO<sub>6</sub> crystallizes in a monoclinic structure P2<sub>1</sub>/n space group, where Zn and Mn atoms are regularly distributed. The Raman spectrum result reveals three peaks at 696 cm<sup>−1</sup>, 655 cm<sup>−1</sup> and 505 cm<sup>−1</sup>, corresponding to the A<sub>g</sub> stretching mode, B<sub>g</sub> anti-stretching, and bending vibrations modes of Ni/Co-O and Mn-O bonds in the structure. The experimental value of the band gap energy was calculated using Tauc’s formula and the result reveals a semiconducting behaviour. We investigated the structural, elastic, magnetic, and electronic properties using the spin-polarized density functional theory. The partial density of state indicates that the material exhibits a antiferromagnetic semiconducting behaviour. The antiferromagnetic ordering is explained by the super-exchange interaction between empty e<sub>g</sub> orbitals of Mn<sup>4+</sup>( <span>({t}_{2 g}^{3})</span><span>({e}_{g}^{0})</span>). The obtained Neel temperature is T<sub>N</sub> ∼ 28 K which is comparable with the experiment results. Elastic constants and their derivative parameters show a high mechanical stability of this material with a ductile nature. The investigation of the transport properties encompassed an analysis of the electrical conductivity, the figure of merit, the Seebeck coefficient, and thermal conductivity. The results show that electronic and thermal conductivities increase linearly with temperature. The computed values of the figure of merit are close to unity, suggesting that this material is a promising candidate for thermoelectric application.</p></div>","PeriodicalId":669,"journal":{"name":"Journal of Superconductivity and Novel Magnetism","volume":"37 8-10","pages":"1541 - 1550"},"PeriodicalIF":1.6,"publicationDate":"2024-06-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141514909","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":"Physical Nature of the Pseudogap Phase and Anomalous Transfer of Spectral Weight in Underdoped Cuprates","authors":"Kirill Mitsen, Olga Ivanenko","doi":"10.1007/s10948-024-06782-x","DOIUrl":"10.1007/s10948-024-06782-x","url":null,"abstract":"<div><p>It is shown that many anomalies observed in underdoped cuprates, including anomalous spectral weight transfer and a large pseudogap, appear to have a common nature due to both the cluster structure of the underdoped phase and the specific mechanism of superconducting pairing. The combined action of these factors leads to the fact that at a temperature <i>T</i> lying in a certain temperature range <i>T</i><sub>c</sub> < <i>T</i> < <i>T</i>*, the crystal contains small isolated clusters that can exist both in superconducting and normal states, randomly switching between them. In this case, below <i>T</i><sub>c</sub> with a very high probability, the cluster is in a superconducting state, and above <i>T</i>*, it is in a normal state, and the interval <i>T</i><sub>c</sub> < <i>T</i> < <i>T</i>* is the region of existence of the so-called pseudogap phase. The temperatures <i>T</i><sub>c</sub> and <i>T</i>* for YBa<sub>2</sub>Cu<sub>3</sub>O<sub>6+δ</sub> were calculated depending on the doping level <i>δ</i>. The calculation results are in good agreement with the experiment without the use of fitting parameters. At a given <i>T</i> in the same temperature range, the time sequence of randomly arising superfluid density pulses from each cluster can be represented as a random process. The effective width Δω<sub>eff</sub> of the spectrum of such a random process will be determined by a correlation time, i.e., the characteristic time between successive on/off superconductivity in two different clusters. This time, according to the estimate, is ~ 10<sup>−15</sup> s, which corresponds to Δω<sub>eff</sub> ~ 1 eV and explains the effect of spectral weight transfer to the high-frequency region. This approach also makes it possible to explain other anomalies observed in the vicinity of <i>T</i><sub>c</sub>: the reversibility of magnetization curves in a certain temperature range below <i>T</i><sub>c</sub>, the anomalous Nernst effect, and anomalous diamagnetism above <i>T</i><sub>c</sub>.</p></div>","PeriodicalId":669,"journal":{"name":"Journal of Superconductivity and Novel Magnetism","volume":"37 5-7","pages":"861 - 872"},"PeriodicalIF":1.6,"publicationDate":"2024-06-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141514910","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}