Physica C-superconductivity and Its Applications最新文献

{"title":"Identification of the nature and mechanism of the zinc doping effect on the normal-state properties of the YBa2Cu3Oy system by a quantitative analysis of the thermopower and Nernst coefficient","authors":"Tammam M. Haddad ,&nbsp;Xunpeng Zhang ,&nbsp;Vitaliy E. Gasumyants","doi":"10.1016/j.physc.2025.1354789","DOIUrl":"10.1016/j.physc.2025.1354789","url":null,"abstract":"<div><div>In this paper, we present the results of an experimental study of the temperature dependences of the thermopower, <em>S</em>, and the Nernst coefficient, <em>Q</em>, in samples of the YBa₂Cu_3-<em>_x</em>Zn<em>_x</em>O<em>_y</em> system with zinc content varying over a wide range. It is shown that, despite the fact that zinc doping has a very slight effect on the absolute values of the transport coefficients at <em>T</em> = 300 K, an increase in its content throughout the entire doping range studied leads to a consistent modification of the <em>S</em>(<em>T</em>) dependences, the nature of which is atypical for the cases of other cation substitutions in the YBa₂Cu₃O<em>_y</em> system. By analyzing the experimental results within the framework of the narrow-band model, we determined the values of the parameters characterizing the energy spectrum structure and charge carrier system properties in samples of different compositions, and then discussed their variations with increasing zinc content. The obtained calculation results clearly show that zinc substituting for the plane copper directly affects the normal-state energy spectrum of the YBa₂Cu₃O<em>_y</em> system, and also make it possible to explain all the observed specific features of the behavior of the transport coefficients in the studied system.</div></div>","PeriodicalId":20159,"journal":{"name":"Physica C-superconductivity and Its Applications","volume":"637 ","pages":"Article 1354789"},"PeriodicalIF":1.0,"publicationDate":"2025-10-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144922475","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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":"Superconductivity in cuprates with planar oxygen vacancies and apical oxygen vacancies","authors":"Yong-Jun Chen","doi":"10.1016/j.physc.2025.1354788","DOIUrl":"10.1016/j.physc.2025.1354788","url":null,"abstract":"<div><div>In this article, we demonstrate superconductivity of cuprates with oxygen deficiency in copper-oxygen planes and apical positions by checking Zhang-Rice singlets (ZRS’s) formation. The oxygen vacancies have different effects on critical temperature (<em>T</em>_c) evolution in underdoped regime and overdoped regime respectively. In the underdoped regime, the oxygen vacancies damage the ZRS formation on its adjacent Cu atoms and suppress the superconductivity identical to effects of impurity substitutions of Cu atoms. However, in the overdoped regime, the oxygen vacancies enhance the <em>T</em>_c which increases with increase of concentration of the oxygen vacancies. The superconductivity persists when the concentration of the oxygen vacancies is larger than 0.50 (per Cu atom) in the copper-oxygen plane. Effects of planar oxygen vacancies and apical vacancies with various concentrations have been examined. The superconductivity in the highly overdoped regime (doping level spans from 0.27 to 0.80) has been predicted. It suggests a new method to discover the new superconductors. Our results can explain post-annealing-induced enhancement of the <em>T</em>_c from 70 K to above 90 K in Sr₂CuO_3+δ with the oxygen vacancies in the copper-oxygen plane and the apical positions.</div></div>","PeriodicalId":20159,"journal":{"name":"Physica C-superconductivity and Its Applications","volume":"637 ","pages":"Article 1354788"},"PeriodicalIF":1.0,"publicationDate":"2025-10-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144913141","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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":"Corrigendum to “Interfacial superconductivity in Cu/Cu2O and its effect on shielding ambient electric fields” [Physica C: Superconductivity and its Applications 632 (2025) 1354600]","authors":"Dale R. Harshman ,&nbsp;Anthony T. Fiory","doi":"10.1016/j.physc.2025.1354752","DOIUrl":"10.1016/j.physc.2025.1354752","url":null,"abstract":"","PeriodicalId":20159,"journal":{"name":"Physica C-superconductivity and Its Applications","volume":"636 ","pages":"Article 1354752"},"PeriodicalIF":1.3,"publicationDate":"2025-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144623657","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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":"Effect of ozone annealing on FeSr2YCu2O6+y superconductor","authors":"Yoshiaki Hata ,&nbsp;Shun Taguchi ,&nbsp;Takashi Mochiku ,&nbsp;Hiroshi Yasuoka","doi":"10.1016/j.physc.2025.1354766","DOIUrl":"10.1016/j.physc.2025.1354766","url":null,"abstract":"<div><div>Polycrystalline <span><math><mrow><msub><mrow><mi>FeSr</mi></mrow><mrow><mn>2</mn></mrow></msub><msub><mrow><mi>YCu</mi></mrow><mrow><mn>2</mn></mrow></msub><msub><mrow><mi>O</mi></mrow><mrow><mn>6</mn><mo>+</mo><mi>y</mi></mrow></msub></mrow></math></span> superconductor was oxidized by ozone to improve its superconducting property. Zero resistivity was observed below <span><math><msubsup><mrow><mi>T</mi></mrow><mrow><mi>c</mi></mrow><mrow><mi>zero</mi></mrow></msubsup></math></span> = 52 K, and diamagnetism was observed below <span><math><msubsup><mrow><mi>T</mi></mrow><mrow><mi>c</mi></mrow><mrow><mi>MT</mi></mrow></msubsup></math></span> = 70 K. After the sample was ozonized, <span><math><msubsup><mrow><mi>T</mi></mrow><mrow><mi>c</mi></mrow><mrow><mi>zero</mi></mrow></msubsup></math></span> and <span><math><msubsup><mrow><mi>T</mi></mrow><mrow><mi>c</mi></mrow><mrow><mi>MT</mi></mrow></msubsup></math></span> increased by 10 and 14 K, respectively. The critical current density in individual grains at 2 K under a 0.1 T field was deduced to be <span><math><mrow><mn>1</mn><mo>.</mo><mn>3</mn><mo>×</mo><mn>1</mn><msup><mrow><mn>0</mn></mrow><mrow><mn>11</mn></mrow></msup><msup><mrow><mi>A/m</mi></mrow><mrow><mn>2</mn></mrow></msup></mrow></math></span> from the magnetization curve, which was 38 times greater than that of a sample annealed under a high <span><math><msub><mrow><mi>O</mi></mrow><mrow><mn>2</mn></mrow></msub></math></span> pressure.</div></div>","PeriodicalId":20159,"journal":{"name":"Physica C-superconductivity and Its Applications","volume":"636 ","pages":"Article 1354766"},"PeriodicalIF":1.0,"publicationDate":"2025-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144737952","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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":"Planckian bounds from local uncertainty relations","authors":"Zohar Nussinov ,&nbsp;Saurish Chakrabarty","doi":"10.1016/j.physc.2025.1354755","DOIUrl":"10.1016/j.physc.2025.1354755","url":null,"abstract":"<div><div>We introduce “<em>local uncertainty relations</em>” in thermal quantum many-body systems from which fundamental bounds can be derived. These inequalities imply rigorous universal non-relativistic speed limits (independent of interaction range) and, as we focus on in the current work, bounds associated with transport (e.g., the diffusion constant and shear viscosity). Using the chaos bounds and other considerations, we introduce simplified non-rigorous universal transport coefficient inequalities and compare our resulting bounds against experimental data.</div></div>","PeriodicalId":20159,"journal":{"name":"Physica C-superconductivity and Its Applications","volume":"636 ","pages":"Article 1354755"},"PeriodicalIF":1.3,"publicationDate":"2025-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144623704","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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 novel (AuxCu1-x)Sr2CaCu2Oy superconductor under high pressure","authors":"Zhenlei Feng ,&nbsp;Thi-Mai-Dung Do ,&nbsp;Tadachika Nakayama ,&nbsp;Tomoya Aoba ,&nbsp;Hisayuki Suematsu ,&nbsp;Koichi Niihara","doi":"10.1016/j.physc.2025.1354777","DOIUrl":"10.1016/j.physc.2025.1354777","url":null,"abstract":"<div><div>A novel superconductor of (AuxCu1-x)Sr2CaCu2Oy ((Au,Cu)-1(Sr)212) was synthesized by oxidation of Au at 5.5 GPa and 980–1030 °C. The crystal structure of (Au,Cu)-1(Sr)212 was analyzed using X-ray diffraction (XRD) and field emission transmission electron microscopy (FE-TEM). From XRD results, the (Au,Cu)-1(Sr)212 with lattice parameters of <em>a</em> ≈ 3.86 Å, <em>c</em> ≈ 10.98 Å, respectively, were observed. A superconducting signal was observed below <em>T</em> = 29.7 K in the magnetic susceptibility measurements.</div></div>","PeriodicalId":20159,"journal":{"name":"Physica C-superconductivity and Its Applications","volume":"636 ","pages":"Article 1354777"},"PeriodicalIF":1.0,"publicationDate":"2025-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144723879","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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":"Unusual electronic structure in underdoped cuprate superconductors","authors":"Xiang Li ,&nbsp;Minghuan Zeng ,&nbsp;Huaiming Guo ,&nbsp;Shiping Feng","doi":"10.1016/j.physc.2025.1354767","DOIUrl":"10.1016/j.physc.2025.1354767","url":null,"abstract":"<div><div>The underdoped cuprate superconductors are characterized by the opening of the normal-state pseudogap, while such an aspect of the normal-state pseudogap effect should be reflected in the low-energy electronic structure. Here the effect of the normal-state pseudogap on the low-energy electronic structure in the underdoped cuprate superconductors is investigated within the framework of the kinetic-energy-driven superconductivity. The strong coupling of the electrons with the spin excitation induces the normal-state pseudogap-state in the particle-hole channel and superconducting (SC) state in the particle–particle channel, where the normal-state pseudogap and SC gap respectively originate from the electron normal and anomalous self-energies, and are evaluated by taking into account the vertex correction. As a natural consequence of the interplay between the normal-state pseudogap-state and SC-state, the SC transition temperature <span><math><msub><mrow><mi>T</mi></mrow><mrow><mi>c</mi></mrow></msub></math></span> exhibits a dome-like shape of the doping dependence, however, in a striking contrast to <span><math><msub><mrow><mi>T</mi></mrow><mrow><mi>c</mi></mrow></msub></math></span> in the underdoped regime, the normal-state pseudogap crossover temperature <span><math><msup><mrow><mi>T</mi></mrow><mrow><mo>∗</mo></mrow></msup></math></span> is much higher than <span><math><msub><mrow><mi>T</mi></mrow><mrow><mi>c</mi></mrow></msub></math></span> in the underdoped regime, and then it decreases with the increase of doping, eventually disappearing together with <span><math><msub><mrow><mi>T</mi></mrow><mrow><mi>c</mi></mrow></msub></math></span> at the end of the SC dome. Concomitantly, the spectral weight on the electron Fermi surface (EFS) at around the antinodal region is suppressed strongly by this normal-state pseudogap, and then EFS is truncated to form four disconnected Fermi arcs centered around the nodal region with the largest spectral weight located at around the tips of the disconnected Fermi arcs. Moreover, the dip in the peak-dip-hump structure observed in the energy distribution curve and checkerboard charge ordering found in the ARPES autocorrelation are intrinsically connected with the emergence of the normal-state pseudogap. The theory therefore indicates that the same spin excitation that governs both the normal-state pseudogap-state and SC-state naturally leads to the exotic features of the low-energy electronic structure in the underdoped cuprate superconductors.</div></div>","PeriodicalId":20159,"journal":{"name":"Physica C-superconductivity and Its Applications","volume":"636 ","pages":"Article 1354767"},"PeriodicalIF":1.3,"publicationDate":"2025-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144678805","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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":"Quantum fisher information reveals UV-IR mixing in the strange metal","authors":"David Bałut ,&nbsp;Xuefei Guo ,&nbsp;Niels de Vries ,&nbsp;Dipanjan Chaudhuri ,&nbsp;Barry Bradlyn ,&nbsp;Peter Abbamonte ,&nbsp;Philip W. Phillips","doi":"10.1016/j.physc.2025.1354750","DOIUrl":"10.1016/j.physc.2025.1354750","url":null,"abstract":"<div><div>The density-density response in optimally doped Bi<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span>Sr<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span>CaCu<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span>O<span><math><msub><mrow></mrow><mrow><mn>8</mn><mo>+</mo><mi>x</mi></mrow></msub></math></span> has recently been shown to exhibit conformal symmetry. Using, the experimentally inferred conformal dynamic susceptibility, we compute the resultant quantum Fisher information (QFI), a witness to multi-partite entanglement. For a Fermi liquid, we find that the QFI grows quadratically as the temperature increases, consistent then with the phase space available for scattering in the standard theory of metals. By contrast, the QFI in a strange metal increases as a power law at as the temperature decreases, but ultimately extrapolates to a constant at <span><math><mrow><mi>T</mi><mo>=</mo><mn>0</mn></mrow></math></span>. The constant is of the form, <span><math><msubsup><mrow><mi>ω</mi></mrow><mrow><mi>g</mi></mrow><mrow><mn>2</mn><mi>Δ</mi></mrow></msubsup></math></span>, where <span><math><mi>Δ</mi></math></span> is the conformal dimension and <span><math><msub><mrow><mi>ω</mi></mrow><mrow><mi>g</mi></mrow></msub></math></span> is the UV cutoff which is on the order of the pseudogap. As this constant depends on both UV and IR properties, it illustrates that multipartite entanglement in a strange metal exhibits UV-IR mixing, a benchmark feature of doped Mott insulators as exemplified by dynamical spectral weight transfer. We conclude with a discussion of the implication of our results for low-energy reductions of the Hubbard model.</div></div>","PeriodicalId":20159,"journal":{"name":"Physica C-superconductivity and Its Applications","volume":"635 ","pages":"Article 1354750"},"PeriodicalIF":1.3,"publicationDate":"2025-08-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144307895","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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":"Superconducting single crystals show about 50% increase of the superconducting critical temperature after Ar Ion implantation","authors":"Kriti Ranjan Sahu ,&nbsp;Thomas Wolf ,&nbsp;A K Mishra ,&nbsp;Keka R Chakraborty ,&nbsp;A Banerjee ,&nbsp;V Ganesan ,&nbsp;Udayan De","doi":"10.1016/j.physc.2025.1354733","DOIUrl":"10.1016/j.physc.2025.1354733","url":null,"abstract":"<div><div>Single crystals of a Fe-based superconductor, Ba(Fe_0.943Co_0.057)₂As₂, with ∼200 μm thickness (t) have been irradiated along the thickness (c-axis) of by 1.5 MeV Ar⁶⁺ ions, having ion range (R) of 0.903 μm (SRIM calculation). Fast ion irradiations damage the lattice of the target, and usually decrease the superconducting critical temperature (T_c), with a few exceptions of small increases. However, our irradiation, a case of ion implantation (R &gt; t), presently to a fluence of 2.5 × 10¹⁵ Ar⁶⁺/cm², increased the onset T_c of the single crystal superconductors by ∼ 8 K from its initial value of ∼ 17 K as measured from the real part of the magnetic susceptibility, matching results from our additional measurements of the imaginary part, electrical resistivity and magnetization. These self-supporting T_c results ensure correctness of the result. To our knowledge, such huge increase of the superconducting critical temperature by ion irradiation has not been reported earlier. Fortunately, we find following explanation, and consider it most appropriate. The insoluble inert gas atoms precipitate often as high-pressure miniature bubbles as is well known from various experiments and also from observations in nuclear reactor walls. This exerts a large compressive strain on the lattice. Our novel explanation is that this additional strain increases T_c by ∼ 49 %. Moreover, the same Ar implantation in non-superconducting BaFe₂As₂ induced 20 K superconductivity. Depending on such bubble formation and their stability in other target-ion pairs, such large T_c enhancement may be discovered in other superconductors, and used with the advantages of higher T_c.</div></div>","PeriodicalId":20159,"journal":{"name":"Physica C-superconductivity and Its Applications","volume":"635 ","pages":"Article 1354733"},"PeriodicalIF":1.3,"publicationDate":"2025-08-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144170427","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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":"How do supercurrents die down when a superconductor goes normal?","authors":"J.E. Hirsch","doi":"10.1016/j.physc.2025.1354747","DOIUrl":"10.1016/j.physc.2025.1354747","url":null,"abstract":"<div><div>The supercurrent flowing near the surface of a type I superconducting body in the presence of an external magnetic field carries kinetic energy and angular momentum. When the macroscopic body transits into the normal state and magnetic field lines start penetrating it, Faraday’s law induces electric currents opposing the change in magnetic flux, that in the aggregate carry kinetic energy and angular momentum many orders of magnitude larger than the supercurrent in the initial state. These currents die down, and their angular momentum is transferred to the body as a whole, without generation of entropy. The conventional theory of superconductivity does not explain how this happens. The alternative theory of hole superconductivity does: it requires carriers with negative effective mass. Our theory also provides an explanation for why flux is generically trapped in type I superconductors under field cooling conditions.</div></div>","PeriodicalId":20159,"journal":{"name":"Physica C-superconductivity and Its Applications","volume":"635 ","pages":"Article 1354747"},"PeriodicalIF":1.3,"publicationDate":"2025-08-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144203418","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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}