Physica C-superconductivity and Its Applications最新文献_第7页

Bending characteristics of multi-layer spiral HTS cable with large tape gap 大带隙多层螺旋高温超导电缆弯曲特性研究

IF 1.3 3区物理与天体物理

Physica C-superconductivity and Its Applications Pub Date : 2025-04-07 DOI: 10.1016/j.physc.2025.1354691

Haosheng Ye, Xuan Zhou, Jie Sheng, Jinshan Yang, Zhijian Jin, Yue Zhao

{"title":"Bending characteristics of multi-layer spiral HTS cable with large tape gap","authors":"Haosheng Ye, Xuan Zhou, Jie Sheng, Jinshan Yang, Zhijian Jin, Yue Zhao","doi":"10.1016/j.physc.2025.1354691","DOIUrl":"10.1016/j.physc.2025.1354691","url":null,"abstract":"<div><div>Assembling high-temperature superconducting (HTS) tapes into robust cable with spiral geometry is widely adopted to achieve high current-carrying capacity and strong mechanical properties in high-field magnet applications. However, multi-layer structure of spiral HTS cable undermines its bending performance due to complex factors, which have not been comprehensively clarified yet. In this paper, the influence of the tape gap on the bending characteristics of double-layer spiral HTS cable has been investigated through both experimental and numerical methods. and we revealed a distinct mechanism of critical current degradation during bending correlated with large tape gap. Result shows that, the large tape gap, as an unneglectable geometrical irregularity, leads to the increment of the interlayer friction coefficient. Moreover, with the increase of tape gap, additional compressive strain would be imposed on tape, leading to the exacerbation of imbalance of strain distribution. Therefore, cable samples with larger tape gap exhibit inferior bending performance compared to those with smaller tape gap, and this earlier occurrence of critical current degradation during bending process is primarily manifested in the outer layer. Conclusion obtained from this paper is anticipated to assist the understanding of the mechanism of bending performance degradation, as well as the improvement of engineering production for multi-layer spiral HTS cable.</div></div>","PeriodicalId":20159,"journal":{"name":"Physica C-superconductivity and Its Applications","volume":"632 ","pages":"Article 1354691"},"PeriodicalIF":1.3,"publicationDate":"2025-04-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143791771","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}

引用次数: 0

Enhanced superconductivity in non-centrosymmetric hexagonal HfRuAs 非中心对称六方HfRuAs的超导性增强

IF 1.3 3区物理与天体物理

Physica C-superconductivity and Its Applications Pub Date : 2025-04-02 DOI: 10.1016/j.physc.2025.1354710

Lijia Zhou , Xin Chen , Guangtong Shan , Qiang Li , Xiaojun Kuang , Xianran Xing

{"title":"Enhanced superconductivity in non-centrosymmetric hexagonal HfRuAs","authors":"Lijia Zhou , Xin Chen , Guangtong Shan , Qiang Li , Xiaojun Kuang , Xianran Xing","doi":"10.1016/j.physc.2025.1354710","DOIUrl":"10.1016/j.physc.2025.1354710","url":null,"abstract":"<div><div>We report the synthesis, crystal structure, superconductivity, and physical properties of HfRuAs, a ternary equiatomic compound that can crystallize in either the TiFeSi-type orthorhombic (o’-phase) or the Fe<sub>2</sub>P-type hexagonal (h-phase) structure. Our synthesized polycrystalline samples exhibit coexistence of both two phases due to synthesis conditions. The h-phase demonstrates bulk type-II weak-coupling superconductivity with a superconducting transition temperature of approximately 7.25 K, and an upper critical field of 12.40 T. Structural refinements suggest that the expansion of Ru-Ru distances within triangular clusters may be associated with the enhancement of superconductivity in the h-phase. First-principles calculations confirm that antisymmetric spin-orbit coupling (ASOC) induces significant band splitting and opens a fully gapped superconducting state. These results indicate that h-phase HfRuAs is a promising candidate for exploring superconductivity in weakly correlated, non-centrosymmetric superconductors.</div></div>","PeriodicalId":20159,"journal":{"name":"Physica C-superconductivity and Its Applications","volume":"633 ","pages":"Article 1354710"},"PeriodicalIF":1.3,"publicationDate":"2025-04-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143791021","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}

引用次数: 0

Holographic Schwinger–Keldysh effective field theories including a non-hydrodynamic mode 包括非水动力模式的全息Schwinger-Keldysh有效场理论

IF 1.3 3区物理与天体物理

Physica C-superconductivity and Its Applications Pub Date : 2025-03-29 DOI: 10.1016/j.physc.2025.1354701

Yan Liu , Ya-Wen Sun , Xin-Meng Wu

引用次数: 0

Universality and crossovers for quantum-criticality in 2d metals 二维金属量子临界的普遍性和交叉性

IF 1.3 3区物理与天体物理

Physica C-superconductivity and Its Applications Pub Date : 2025-03-26 DOI: 10.1016/j.physc.2025.1354703

Chandra M. Varma

{"title":"Universality and crossovers for quantum-criticality in 2d metals","authors":"Chandra M. Varma","doi":"10.1016/j.physc.2025.1354703","DOIUrl":"10.1016/j.physc.2025.1354703","url":null,"abstract":"<div><div>A simple generalization of the theory of crossovers in classical-criticality to quantum-criticality gives that, a Heisenberg model with a small anisotropy favoring planar order has a cross-over towards the fixed point of the xy model in the temperature direction which is very rapid compared to those in the orthogonal directions, if the temporal correlation length is much larger than the spatial correlation length, i.e. for a large dynamic exponent <span><math><mi>z</mi></math></span>. At the other end of the flow, the stability of the fixed point of the quantum xy model coupled to fermions is exponentially enhanced in the temperature direction. This is used to explain why the quantum-critical fluctuations of all measured 2d anti-ferromagnetic compounds — cuprates, heavy-fermion and Fe-based metals shows the characteristic fluctuations of the quantum xy model, and have the same anomalous transport and thermodynamic properties as the cuprates and twisted WSe<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span> and Graphene. We segue briefly to the range of extended quantum-criticality due to disorder by generalizing the Harris criteria as well, using the properties of the quantum xy model. The observed <span><math><mrow><mi>T</mi><mo>ln</mo><mi>T</mi></mrow></math></span> specific heat at criticality is derived quite simply using the same methods which derive the cross-overs.</div><div>This paper is written for the commemoration volume for Jan Zaanen whom I knew very well, starting from his days as a post-doc at Bell labs to his career as a distinguished Professor at Leiden. Despite a complete difference in the approach towards the problems of our common interest later, we remained very good friends.</div></div>","PeriodicalId":20159,"journal":{"name":"Physica C-superconductivity and Its Applications","volume":"633 ","pages":"Article 1354703"},"PeriodicalIF":1.3,"publicationDate":"2025-03-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143777515","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}

引用次数: 0

Origin of the reentrant tetragonal phase in hole-doped Fe-pnictide superconductors: Role of intersite Coulomb interaction 空穴掺杂铁镍超导体中可重入四方相的起源：场间库仑相互作用的作用

IF 1.3 3区物理与天体物理

Physica C-superconductivity and Its Applications Pub Date : 2025-03-22 DOI: 10.1016/j.physc.2025.1354699

Hao Luo, Huan Li, Xing Ming, Xiao-Jun Zheng

{"title":"Origin of the reentrant tetragonal phase in hole-doped Fe-pnictide superconductors: Role of intersite Coulomb interaction","authors":"Hao Luo, Huan Li, Xing Ming, Xiao-Jun Zheng","doi":"10.1016/j.physc.2025.1354699","DOIUrl":"10.1016/j.physc.2025.1354699","url":null,"abstract":"<div><div>Using mean-field approaches within the extended five-orbital Hubbard model, we reveal that intersite Coulomb interactions play a crucial role in determining the distinct magnetic phases of iron-based superconductors. We demonstrate that the reentrant tetragonal (<span><math><msub><mrow><mi>C</mi></mrow><mrow><mn>4</mn></mrow></msub></math></span>) phase, which is a spin charge density wave (SCDW) phase, is a combination of the stripe-like antiferromagnetic phase (str-AFM) and the charge density wave (CDW) phase. We prove that SCDW is the ground state in the hole-doped Fe-pnictides as long as the intersite Coulomb interaction (<span><math><mi>V</mi></math></span>) increases with doping concentration. Our work not only provides a numerical realization of the reentrant <span><math><msub><mrow><mi>C</mi></mrow><mrow><mn>4</mn></mrow></msub></math></span> state but also emphasizes the significant role of intersite interactions in the emergence of this phase, offering a deep understanding into the complex diagram phase of iron-based materials.</div></div>","PeriodicalId":20159,"journal":{"name":"Physica C-superconductivity and Its Applications","volume":"632 ","pages":"Article 1354699"},"PeriodicalIF":1.3,"publicationDate":"2025-03-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143681880","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}

引用次数: 0

Superconducting correlations in the asymmetric Hubbard model 非对称哈伯德模型中的超导相关性

IF 1.3 3区物理与天体物理

Physica C-superconductivity and Its Applications Pub Date : 2025-03-18 DOI: 10.1016/j.physc.2025.1354693

Pavol Farkašovský

{"title":"Superconducting correlations in the asymmetric Hubbard model","authors":"Pavol Farkašovský","doi":"10.1016/j.physc.2025.1354693","DOIUrl":"10.1016/j.physc.2025.1354693","url":null,"abstract":"<div><div>The projector Quantum-Monte-Carlo method is used to examine effects of down-spin electron hopping <span><math><msub><mrow><mi>t</mi></mrow><mrow><mi>↓</mi></mrow></msub></math></span> and the on-site interaction <span><math><mi>U</mi></math></span> between the up and down spin electrons on superconducting correlations in the two-dimensional asymmetric Hubbard model. It is shown that both, the down-spin electron hopping, as well as the on-site interaction strongly enhance the superconducting correlations in the <span><math><mi>d</mi></math></span>-wave channel. The most significant enhancement of superconducting correlations, by down-spin electron hopping, is found for electron concentrations near the half-filled band case where, in addition, the strong connection between the diagonal charge stripes and the superconducting correlations is observed and the increasing on-site interaction <span><math><mi>U</mi></math></span> further enhances this effect. The enhancement of superconducting correlations is observed also in the axial striped phase, while it is negligible in the segregated phase. This opens new route to understanding the relation between the inhomogeneous charge ordering and superconductivity in strongly correlated electron systems.</div></div>","PeriodicalId":20159,"journal":{"name":"Physica C-superconductivity and Its Applications","volume":"632 ","pages":"Article 1354693"},"PeriodicalIF":1.3,"publicationDate":"2025-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143644296","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}

引用次数: 0

Thermal transmittance measurements of niobium at cryogenic temperatures 铌在低温下的热透射率测量结果

IF 1.3 3区物理与天体物理

Physica C-superconductivity and Its Applications Pub Date : 2025-03-12 DOI: 10.1016/j.physc.2025.1354694

Marc Wenskat , Leon King , Lasse Koch , Cem Saribal , Anton Lorf , Isabel González Díaz-Palacio , Cornelius Martens , Robert Zierold , Wolfgang Hillert

{"title":"Thermal transmittance measurements of niobium at cryogenic temperatures","authors":"Marc Wenskat , Leon King , Lasse Koch , Cem Saribal , Anton Lorf , Isabel González Díaz-Palacio , Cornelius Martens , Robert Zierold , Wolfgang Hillert","doi":"10.1016/j.physc.2025.1354694","DOIUrl":"10.1016/j.physc.2025.1354694","url":null,"abstract":"<div><div>The first <span><math><mi>O</mi></math></span>(100snm) of the inner surface Niobium-based superconducting RF (SRF) cavities are crucial to achieve high accelerating fields and a low surface resistance. Recent treatments aim to improve superconducting properties by tailoring the interstitial atom concentration or by depositing thin superconducting films. Yet, no investigation of the thermal characteristics of those surfaces after such treatments has been done, although this is a crucial property to cool the induced RF losses away and to maintain the superconducting state while high surface magnetic fields are applied. In this contribution, a newly developed experimental set-up is described, which allowed the first ever measurement of the thermal transmittance of Mid-T heat treated and Superconductor-Insulator-Superconductor (SIS) coated niobium samples. The results show that the SIS samples perform the same as standard niobium and that Mid-T heat treated samples have an improved thermal transmittance of 30%.</div></div>","PeriodicalId":20159,"journal":{"name":"Physica C-superconductivity and Its Applications","volume":"632 ","pages":"Article 1354694"},"PeriodicalIF":1.3,"publicationDate":"2025-03-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143628100","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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}

引用次数: 0

Effect of temperature and spinning speed on texture in spin-coated Sm2Zr2O7 buffer layer on Ni-5 at.%W RABiTS for coated conductors 温度和纺丝速度对Ni-5 at自旋涂覆Sm2Zr2O7缓冲层织构的影响。涂覆导体用%W RABiTS

IF 1.3 3区物理与天体物理

Physica C-superconductivity and Its Applications Pub Date : 2025-03-12 DOI: 10.1016/j.physc.2025.1354669

M. Nandana Nandakumar , Rahul Raj , M.S. Ramachandra Rao , Deepak Kumar , Satyam Suwas , N. Harish Kumar

{"title":"Effect of temperature and spinning speed on texture in spin-coated Sm2Zr2O7 buffer layer on Ni-5 at.%W RABiTS for coated conductors","authors":"M. Nandana Nandakumar , Rahul Raj , M.S. Ramachandra Rao , Deepak Kumar , Satyam Suwas , N. Harish Kumar","doi":"10.1016/j.physc.2025.1354669","DOIUrl":"10.1016/j.physc.2025.1354669","url":null,"abstract":"<div><div>The usage of Rolling Assisted Biaxially Textured Substrates (RABiTS) is a versatile method to produce High-Temperature Superconductor (HTS) based coated conductors. We have investigated, for the first time, the texture evolution of the Sm<sub>2</sub>Zr<sub>2</sub>O<sub>7</sub> (SZO) barrier layer produced by spin coating on Ni-5 at.%W (Ni5W) RABiTS to create a biaxially textured buffer layer architecture. The annealing temperature and spinning speed which are the important film deposition parameters, were varied and their effect on the texture of the film has been investigated to obtain the optimum conditions required for the growth of highly textured film with sufficient thickness. Textured growth of SZO film could be seen across a wide range of substrate temperatures by X-ray diffraction (XRD) based studies. The microstructural investigations were executed using a Scanning Electron Microscope (SEM) and Atomic Force Microscope (AFM). The findings indicate that the annealing temperature and spinning speed affect the films' growth orientation and surface morphology. The XRD (φ scan and ω scan) studies have shown the ability to realise the SZO buffer layer with strong in-plane and out-of-plane texture and a c-axis oriented growth on Ni5W substrate by chemical solution deposition (CSD).</div></div>","PeriodicalId":20159,"journal":{"name":"Physica C-superconductivity and Its Applications","volume":"631 ","pages":"Article 1354669"},"PeriodicalIF":1.3,"publicationDate":"2025-03-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143600852","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}

引用次数: 0

Effect of winding pitches on dynamic resistance of CICC made from CORCs 绕组螺距对CORCs制ccic动态电阻的影响

IF 1.3 3区物理与天体物理

Physica C-superconductivity and Its Applications Pub Date : 2025-03-12 DOI: 10.1016/j.physc.2025.1354681

Liguang Hu , Xuhui Xu , Bibo Zhou , Xian Chen , Qi Cheng , Bangzhu Wang , Junhua Cheng

{"title":"Effect of winding pitches on dynamic resistance of CICC made from CORCs","authors":"Liguang Hu , Xuhui Xu , Bibo Zhou , Xian Chen , Qi Cheng , Bangzhu Wang , Junhua Cheng","doi":"10.1016/j.physc.2025.1354681","DOIUrl":"10.1016/j.physc.2025.1354681","url":null,"abstract":"<div><div>The second generation (2G) high temperature superconducting (HTS) REBCO tapes, presently a unique possible candidate for use in future large high field magnets above 25 T, are promising choice for high capacity current cable-in-conduit conductor (CICC) used in large high field magnets of fusion and power transmissions. Generally, HTS based CICCs are made from several HTS cables or strands consisting of individual REBCO tapes. A configuration of CICC is proposed, which is made from six conductor on round core cables (CORCs) with symmetrically helical winding on a petal copper former. The cooling medium flows in central channels of former and six CORCs, respectively. Although the CICCs generally operate in DC mode, they inevitable endure AC influence at least in charging and discharging process or even ripple current. Consequently, the dynamic resistance appears, which not only generates additional AC loss but also importantly causes nonuniform current distribution and instability. This paper employs analytical model and numerical simulations to investigate the dynamic resistance characteristics of CORC and CICC conductors with different winding pitches respectively. An analytical model is established based on the rotating magnetic field method to efficiently compute the dynamic resistance of single-layer CORC and CICC. Subsequently, three-dimensional (3D) models of CORC and CICC with different winding pitches are established. Using finite element method, the influence of winding pitches on dynamic resistance are calculated based on the T-A formulation. Numerical simulation results are consistent with analytical calculations, demonstrating that winding pitch has a significant impact on dynamic resistance. This study can provide valuable reference for the design of large-scale high field magnets.</div></div>","PeriodicalId":20159,"journal":{"name":"Physica C-superconductivity and Its Applications","volume":"631 ","pages":"Article 1354681"},"PeriodicalIF":1.3,"publicationDate":"2025-03-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143600854","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}

引用次数: 0

Quantum criticality of type-I and critically tilted Dirac semimetals i型和临界倾斜狄拉克半金属的量子临界性

IF 1.3 3区物理与天体物理

Physica C-superconductivity and Its Applications Pub Date : 2025-03-12 DOI: 10.1016/j.physc.2025.1354687

Huanzhi Hu , Frank Krüger

{"title":"Quantum criticality of type-I and critically tilted Dirac semimetals","authors":"Huanzhi Hu , Frank Krüger","doi":"10.1016/j.physc.2025.1354687","DOIUrl":"10.1016/j.physc.2025.1354687","url":null,"abstract":"<div><div>We investigate the universality of an Ising symmetry breaking phase transition of tilted two-dimensional Dirac fermions, in the type-I phase as well as at the Lifshitz transition between a type-I and a type-II semimetal, where the Fermi surface changes from point-like to one with electron and hole pockets that touch at the overtilted Dirac cones. We compute the Landau damping of long-wavelength order parameter fluctuations by tilted Dirac fermions and use the resulting IR propagator as input for a renormalisation-group analysis of the resulting Gross–Neveu–Yukawa field theory. We first demonstrate that the criticality of tilted type-I fermions is controlled by a line of fixed points along which the poles of the renormalised Green function correspond to an untilted Dirac spectrum with varying anisotropy of Fermi velocities. At the phase transition the Lorentz invariance is restored, resulting in the same critical exponents as for conventional Dirac systems. The multicritical point is given by the endpoint of the fixed-point line. It can be approached along any path in parameter space that avoids the fixed point line of the critical type-I semimetal. We show that the critical exponents at the Lifshitz point are different and that Lorentz invariance is broken.</div></div>","PeriodicalId":20159,"journal":{"name":"Physica C-superconductivity and Its Applications","volume":"632 ","pages":"Article 1354687"},"PeriodicalIF":1.3,"publicationDate":"2025-03-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143600739","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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}

引用次数: 0