Physica C-superconductivity and Its Applications最新文献

{"title":"Electromechanical behavior of a rectangular bulk superconductor with an inhomogeneous critical current density under pulsed-field magnetization","authors":"Yu Yang ,&nbsp;Lingyun Jian","doi":"10.1016/j.physc.2024.1354483","DOIUrl":"10.1016/j.physc.2024.1354483","url":null,"abstract":"<div><p>Bulk high-temperature superconductors are widely used in various superconducting devices for their high critical current density and the ability to trap large magnetic field. In some applications, bulk superconductors can be arranged in an array structure to increase the magnetic field strength. However, rectangular bulk superconductors can be arranged more compactly than commonly used cylindrical bulk superconductors. The unique shape of rectangular bulk superconductors results in different distributions of electromagnetic fields, temperature, and stress under a pulsed-field magnetization (PFM) than for cylindrical bulk superconductors. In bulk superconductors, growth sector boundaries and growth sector regions have different critical current density, resulting in an uneven critical current density. Therefore, in this study, the electromagnetic and mechanical behavior of non-uniform rectangular bulk superconductors during the PFM process is investigated. The corresponding distribution and variation in the magnetic field, current, temperature, and stress in the bulk are calculated and analyzed. The influence of rectangle aspect ratio on the electromagnetic and mechanical behavior is discussed. The calculation results show that the magnetic flux jumps occur accompanied by sudden changes in the temperature and pressure. The effect of the aspect ratio of rectangular bulk superconductors on their electromagnetic and mechanical properties is analyzed. The influence of preexisting cracks in a non-uniform rectangular bulk superconductor on the simulation results is discussed. The numerical results indicate that the presence of an edge crack exacerbates the magnetic flux jump as well as the jumps in the temperature and stress. However, a central crack has a relatively small effect on the stability of a bulk superconductor.</p></div>","PeriodicalId":20159,"journal":{"name":"Physica C-superconductivity and Its Applications","volume":"619 ","pages":"Article 1354483"},"PeriodicalIF":1.7,"publicationDate":"2024-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140046790","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":"Effects of Rashba and Dresselhaus spin-orbit couplings on the critical temperature and paramagnetic limiting field of superconductors with broken inversion symmetry","authors":"H. Yavari,&nbsp;M. Tayebantayeba","doi":"10.1016/j.physc.2024.1354465","DOIUrl":"https://doi.org/10.1016/j.physc.2024.1354465","url":null,"abstract":"<div><p>Transition temperature (T_c) and paramagnetic limiting of a superconductor without spatial inversion symmetry in the presence of both Rashba and Dresselhaus antisymmetric spin-orbit couplings is studied. The critical temperature is derived for anisotropy of the superconducting order parameter, ranging from isotropic s-wave to any pairing state with nonzero angular momentum and mixed parity singlet-triplet states emerge due to spin-orbit coupling (SOC). It will be shown that for unprotected odd parity pairing, pure Rashba and Dresselhaus SOCs have similar effects on the reduction of T_c and for combined effects of the two spin-orbit couplings at fixed SOC, T_c reduced by increasing Dresselhaus component and decreased down to its minimum value in the equal-Rashba-Dresselhaus case. The paramagnetic limiting is also analyzed for spin-singlet pairing and it is shown that the low temperature divergence behavior of paramagnetic limiting is less affected by both Rashba and Dresselhaus SOCs but for fixed SOC strength by increasing Dresselhaus component the paramagnetic limiting field is increased.</p></div>","PeriodicalId":20159,"journal":{"name":"Physica C-superconductivity and Its Applications","volume":"619 ","pages":"Article 1354465"},"PeriodicalIF":1.7,"publicationDate":"2024-02-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139999107","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":"Bending characteristics of a round strand made by stacked HTS tapes","authors":"X.Q. Lai ,&nbsp;P.Y. Li ,&nbsp;J.X. Zuo ,&nbsp;L.Y. Sun ,&nbsp;H.H. Wei","doi":"10.1016/j.physc.2024.1354446","DOIUrl":"https://doi.org/10.1016/j.physc.2024.1354446","url":null,"abstract":"<div><p>Although the development of REBCO coated conductor has proved its superiority of critical current in high-field background, mechanical issues caused by electromagnetic forces are still big challenges. Large-scale magnets call for robust and high-J_e cables for simplicity of the system. To meet the requirements, here we report a round cable comprised of a stack of 2 mm wide high-temperature superconducting (HTS) tapes inserted into a copper tube and all soldered with Sn₆₃Pb₃₇. The two prepared samples include five HTS tapes and four copper strips in untwisted manner. Self-field critical current at 77 K was analyzed both numerically and experimentally. The characteristics of in-plane (hard) and out-of-plane (easy) bending were analyzed by finite element method (FEM) and compared to experimental measurements. Good agreement was found between the analysis and experimental results on critical bending radius, which is about 200–215 mm. Our results indicate the robustness of the round strand and its potential for use in large-scale magnets.</p></div>","PeriodicalId":20159,"journal":{"name":"Physica C-superconductivity and Its Applications","volume":"618 ","pages":"Article 1354446"},"PeriodicalIF":1.7,"publicationDate":"2024-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139986437","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":"A novel numerical method to evaluate the heat transfer characteristics of complicated CICC structures","authors":"Fengyang Han ,&nbsp;Zhifan Liu ,&nbsp;Zhifeng Liu ,&nbsp;Qiyong Zhang ,&nbsp;Xiaohong Wang ,&nbsp;Min Wang","doi":"10.1016/j.physc.2023.1354435","DOIUrl":"https://doi.org/10.1016/j.physc.2023.1354435","url":null,"abstract":"&lt;div&gt;&lt;p&gt;In this article, we propose a numerical model for calculating the external heat transfer coefficient between the bundle region and its wall for cables in conduit conductor (CICC). With the assumption of local thermal equilibrium, one macro equation describing the steady heat transfer on the cross section of the CICC can be obtained. A key parameter, the effective transverse thermal conductivity &lt;span&gt;&lt;math&gt;&lt;msub&gt;&lt;mi&gt;k&lt;/mi&gt;&lt;mtext&gt;eff&lt;/mtext&gt;&lt;/msub&gt;&lt;/math&gt;&lt;/span&gt;, which takes the contribution of both strands and flowing fluid into consideration, is introduced. To calculate the effective transverse thermal conductivity &lt;span&gt;&lt;math&gt;&lt;msub&gt;&lt;mi&gt;k&lt;/mi&gt;&lt;mtext&gt;eff&lt;/mtext&gt;&lt;/msub&gt;&lt;/math&gt;&lt;/span&gt;, we first obtain the true distribution of different phases (fluid, copper and superconducting material) on a cross section of CICC with the help of the image recognition technique. Based on this, the value of the effective transverse thermal conductivity &lt;span&gt;&lt;math&gt;&lt;msub&gt;&lt;mi&gt;k&lt;/mi&gt;&lt;mtext&gt;eff&lt;/mtext&gt;&lt;/msub&gt;&lt;/math&gt;&lt;/span&gt; can be calculated numerically. Due to the large difference among the component thermal conductivities (at 4.5 K, typical values of the thermal conductivity of liquid helium, superconducting material and copper are &lt;span&gt;&lt;math&gt;&lt;mrow&gt;&lt;msub&gt;&lt;mi&gt;k&lt;/mi&gt;&lt;mtext&gt;He&lt;/mtext&gt;&lt;/msub&gt;&lt;mo&gt;=&lt;/mo&gt;&lt;mn&gt;0.024&lt;/mn&gt;&lt;mrow&gt;&lt;mspace&gt;&lt;/mspace&gt;&lt;mi&gt;W&lt;/mi&gt;&lt;mspace&gt;&lt;/mspace&gt;&lt;/mrow&gt;&lt;msup&gt;&lt;mrow&gt;&lt;mi&gt;m&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mo&gt;−&lt;/mo&gt;&lt;mn&gt;1&lt;/mn&gt;&lt;/mrow&gt;&lt;/msup&gt;&lt;mspace&gt;&lt;/mspace&gt;&lt;msup&gt;&lt;mrow&gt;&lt;mi&gt;K&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mo&gt;−&lt;/mo&gt;&lt;mn&gt;1&lt;/mn&gt;&lt;/mrow&gt;&lt;/msup&gt;&lt;/mrow&gt;&lt;/math&gt;&lt;/span&gt;, &lt;span&gt;&lt;math&gt;&lt;mrow&gt;&lt;msub&gt;&lt;mi&gt;k&lt;/mi&gt;&lt;mrow&gt;&lt;mi&gt;N&lt;/mi&gt;&lt;msub&gt;&lt;mi&gt;b&lt;/mi&gt;&lt;mn&gt;3&lt;/mn&gt;&lt;/msub&gt;&lt;mtext&gt;Sn&lt;/mtext&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;mo&gt;=&lt;/mo&gt;&lt;mn&gt;0.04&lt;/mn&gt;&lt;mrow&gt;&lt;mspace&gt;&lt;/mspace&gt;&lt;mi&gt;W&lt;/mi&gt;&lt;mspace&gt;&lt;/mspace&gt;&lt;/mrow&gt;&lt;msup&gt;&lt;mrow&gt;&lt;mi&gt;m&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mo&gt;−&lt;/mo&gt;&lt;mn&gt;1&lt;/mn&gt;&lt;/mrow&gt;&lt;/msup&gt;&lt;mspace&gt;&lt;/mspace&gt;&lt;msup&gt;&lt;mrow&gt;&lt;mi&gt;K&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mo&gt;−&lt;/mo&gt;&lt;mn&gt;1&lt;/mn&gt;&lt;/mrow&gt;&lt;/msup&gt;&lt;/mrow&gt;&lt;/math&gt;&lt;/span&gt; and &lt;span&gt;&lt;math&gt;&lt;mrow&gt;&lt;msub&gt;&lt;mi&gt;k&lt;/mi&gt;&lt;mtext&gt;Cu&lt;/mtext&gt;&lt;/msub&gt;&lt;mo&gt;=&lt;/mo&gt;&lt;mn&gt;708&lt;/mn&gt;&lt;mrow&gt;&lt;mspace&gt;&lt;/mspace&gt;&lt;mi&gt;W&lt;/mi&gt;&lt;mspace&gt;&lt;/mspace&gt;&lt;/mrow&gt;&lt;msup&gt;&lt;mrow&gt;&lt;mi&gt;m&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mo&gt;−&lt;/mo&gt;&lt;mn&gt;1&lt;/mn&gt;&lt;/mrow&gt;&lt;/msup&gt;&lt;mspace&gt;&lt;/mspace&gt;&lt;msup&gt;&lt;mrow&gt;&lt;mi&gt;K&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mo&gt;−&lt;/mo&gt;&lt;mn&gt;1&lt;/mn&gt;&lt;/mrow&gt;&lt;/msup&gt;&lt;/mrow&gt;&lt;/math&gt;&lt;/span&gt;; and the maximal ratio of thermal conductivity can be as high as about 30,000), the high-performance finite analytical method (FAM) is recommended to calculate &lt;span&gt;&lt;math&gt;&lt;msub&gt;&lt;mi&gt;k&lt;/mi&gt;&lt;mtext&gt;eff&lt;/mtext&gt;&lt;/msub&gt;&lt;/math&gt;&lt;/span&gt;. After obtaining the effective transverse thermal conductivity &lt;span&gt;&lt;math&gt;&lt;msub&gt;&lt;mi&gt;k&lt;/mi&gt;&lt;mtext&gt;eff&lt;/mtext&gt;&lt;/msub&gt;&lt;/math&gt;&lt;/span&gt; of the bundle region, the heat transfer coefficient can be calculated directly by solving a simple Poisson equation under proper boundary conditions. Two case studies are performed, including the JT-60 Super Advanced (JT-60SA) CICC and the dual channel International Thermonuclear Experimental Reactor, Toroidal Field Performance Sample (ITER-TFPS). The calculated values of heat transfer coefficie","PeriodicalId":20159,"journal":{"name":"Physica C-superconductivity and Its Applications","volume":"618 ","pages":"Article 1354435"},"PeriodicalIF":1.7,"publicationDate":"2024-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139986549","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":"Temperature reduction of an HTS transformer under short circuit fault by modifying the cryostat structure: Impact of Perlator and valve location","authors":"Mahdi Mahamed ,&nbsp;Seyyedmeysam Seyyedbarzegar","doi":"10.1016/j.physc.2023.1354429","DOIUrl":"https://doi.org/10.1016/j.physc.2023.1354429","url":null,"abstract":"<div><p>High Temperature Superconducting (HTS) transformers are one of the potential technologies for power systems connected to offshore wind farms and stand-alone and bulk power grids. In such systems, proper fault performance of any electric device including HTS transformer is a vital factor to ensure a safe, and reliable delivery of electric power as well as power quality in electric grid. Short circuits can increase the risk of developing hot spots in superconducting tapes and as a consequence burning the windings in severe fault current cases. One important way to limit the temperature increase of the superconducting winding during short circuit is to increase the heat transfer of the liquid nitrogen (LN₂) during fault. In this paper, the impact of increasing the turbulence of the inlet fluid on the Hot Spot Point (HSP) temperature of superconducting windings of a 120 kVA HTS transformer was investigated during a short circuit fault. To increase turbulence and consequently, heat transfer, a device known as Perlator was used. Then, the impact of the Perlator structure and the location and angle of inlet valves were investigated on the HSP temperature of an HTS transformer, under 65 K and 77 K operating temperatures. The results indicated that by using a Perlator and adjusting valve number and location in the cryostat structure, the HSP temperature of the HTS transformer under the fault current was significantly reduced by about 46.2 K which can be vital to save the transformer from failure.</p></div>","PeriodicalId":20159,"journal":{"name":"Physica C-superconductivity and Its Applications","volume":"618 ","pages":"Article 1354429"},"PeriodicalIF":1.7,"publicationDate":"2024-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139985717","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":"Influences of oxygen partial pressure on the phase composition of the (Bi, Pb)-2212 precursor powder","authors":"Wen Zhang ,&nbsp;Shengnan Zhang ,&nbsp;Hao Cao ,&nbsp;Botao Shao ,&nbsp;Xueqian Liu ,&nbsp;Jixing Liu ,&nbsp;Qing Yang ,&nbsp;Chengshan Li ,&nbsp;Pingxiang Zhang","doi":"10.1016/j.physc.2024.1354448","DOIUrl":"https://doi.org/10.1016/j.physc.2024.1354448","url":null,"abstract":"<div><p>Bi-2223 tapes, synthesized through the two-powder method, exhibit distinctive features such as high current density and a controllable secondary phase. Traditionally, the two-powder method involves the separate preparation of Bi-2212 and Ca<img>Cu<img>O powders followed by their mixing. However, during this process, it is necessary to dope the Bi-2212 powder with an appropriate Pb content to achieve a stable lattice structure in the Bi-2223 phase. The alteration of ion valences between Pb²⁺ and Pb⁴⁺ influences the oxygen content, thereby affecting the phase formation of (Bi, Pb)-2212 and, consequently, the final properties of Bi-2223 tapes. Surprisingly, limited research has explored the impact of the heat treatment process on (Bi, Pb)-2212. Consequently, this study investigates the phase composition and microstructure of (Bi, Pb)-2212 under various oxygen partial pressures to deepen our understanding of the effect of Pb on the composition of (Bi, Pb)-2212. Simultaneously, the behavior of Pb in the lattice of Bi-2212 is analyzed. Ultimately, the findings reveal that low oxygen conditions are advantageous for fabricating (Bi, Pb)-2212 powder with a high main phase content and a reduced secondary phase, thereby demonstrating excellent current-carrying performance in Bi-2223 tapes.</p></div>","PeriodicalId":20159,"journal":{"name":"Physica C-superconductivity and Its Applications","volume":"618 ","pages":"Article 1354448"},"PeriodicalIF":1.7,"publicationDate":"2024-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139986436","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":"Design and experiment of conduction cooling HTS current leads suited for superconducting Wiggler magnets","authors":"Haifeng Zhang ,&nbsp;Guangli Kuang ,&nbsp;Weiming Li ,&nbsp;Junjie Li ,&nbsp;Huaikuang Ding ,&nbsp;Xuehua Zhang","doi":"10.1016/j.physc.2023.1354433","DOIUrl":"https://doi.org/10.1016/j.physc.2023.1354433","url":null,"abstract":"<div><p>The cryogenic system of the 6T superconducting Wiggler magnets at the Hefei National Synchrotron Radiation Laboratory was upgraded. During the upgrade process, the original copper leads of the superconducting Wiggler magnets are replaced with two 460A high-temperature superconducting current leads and three 20A high-temperature superconducting current leads, reducing the heat load of the cryogenic system. Five HTS current leads can be cooled using a GM cryocooler based on the optimal design and experimental verification of their current-carrying capability and heat load. According to the loading current experimental data, the running voltage and operating temperature are stable. The results of the overcurrent capacity experiments demonstrate that the maximum loading current of the 20A high-temperature superconducting current lead can reach 142A and that of the 460A high-temperature superconducting current lead can reach 780A.</p></div>","PeriodicalId":20159,"journal":{"name":"Physica C-superconductivity and Its Applications","volume":"618 ","pages":"Article 1354433"},"PeriodicalIF":1.7,"publicationDate":"2024-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139985954","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":"The improved model based on the H-A formulation in large-scale HTS magnet","authors":"Xiaoyu Ji,&nbsp;Benzhe Zhou,&nbsp;Yong Chen,&nbsp;Shixian Liu,&nbsp;Qiuliang Wang,&nbsp;Jianhua Liu","doi":"10.1016/j.physc.2023.1354431","DOIUrl":"https://doi.org/10.1016/j.physc.2023.1354431","url":null,"abstract":"<div><p>The rapid progression of the rare earth barium copper oxide (REBCO) coated conductor have paved the way for the development of high-field superconducting magnets. However, the elevated aspect ratio of REBCO tapes results in the generation of substantial screening currents, presenting a formidable challenge in the electromagnetic analysis of high-field superconducting magnets. Currently, the finite element method (FEM) stands as the dominant technique employed in large-scale superconducting magnet system for screening current computations in REBCO tapes, encompassing primarily the H formulation and the T-A formulation. However, these models exhibit certain limitations. In this paper, the two-dimensional axisymmetric H-A FEM model is introduced into the computation of REBCO tapes in high-field magnet, and the corresponding homogeneous model, partial homogeneous model and multi-scale model are established. It can be demonstrated that the model not only significantly accelerates computational speed but also enhances precision in comparison to the T-A model. Remarkably, the computational time of the H-A homogeneous model is approximately a quarter of that required by the T-A homogeneous model. It is anticipated that the model harbors substantial potential for future applications in the computational analysis of large-scale superconducting magnets.</p></div>","PeriodicalId":20159,"journal":{"name":"Physica C-superconductivity and Its Applications","volume":"618 ","pages":"Article 1354431"},"PeriodicalIF":1.7,"publicationDate":"2024-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139985953","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":"Electromagnetic response analysis of high temperature superconducting coated conductor tape with local debonding: Case of transporting current in an external magnetic field","authors":"Yumei Yang ,&nbsp;Pengpeng Wu ,&nbsp;Haijun Lou ,&nbsp;Zhipeng Li ,&nbsp;Fangming Lei","doi":"10.1016/j.physc.2024.1354469","DOIUrl":"https://doi.org/10.1016/j.physc.2024.1354469","url":null,"abstract":"<div><p>In this article, the electromagnetic mechanical behavior of a long superconducting coating tape within a local internal cracking was analyzed when it transport current in a perpendicular magnetic field. Based on the superconducting critical state model, the distribution of current and magnetic field within the structure were calculated. Then, the control equation for the correlation between the flux pinning force inside the superconducting thin film and the shear force at the substrate interface was given using the plane strain method of linear elasticity theory. Combined with the Chebyshev polynomial solution, the distribution patterns of normal stress inside the superconducting thin film and shear stress at the substrate interface were finally obtained. The results indicate that, unlike the phenomenon observed under a single field excitation, the stress distribution in the structure exhibits an asymmetric distribution when both transport current and external magnetic field are applied. The normal stress inside the superconducting thin film is significantly larger on the right side of the structure than that on the left side, and the same distribution law is found in the shear stress at the substrate interface. The stress concentration occurs at the separation point between the film and the substrate. When the Young's modulus of the substrate material is high, the normal stress inside the superconducting film is low, while the shear stress at the interface is high, and vice versa. All these results provide theoretical guidance for the application of superconducting tapes.</p></div>","PeriodicalId":20159,"journal":{"name":"Physica C-superconductivity and Its Applications","volume":"618 ","pages":"Article 1354469"},"PeriodicalIF":1.7,"publicationDate":"2024-02-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139915116","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":"Flux creep regimes and vortex phase diagram in β-FeSe single crystals","authors":"L. Lanoël ,&nbsp;N. Haberkorn ,&nbsp;G. Nieva","doi":"10.1016/j.physc.2024.1354466","DOIUrl":"10.1016/j.physc.2024.1354466","url":null,"abstract":"<div><p>We analyze the relationship between critical current densities (<em>J_C</em>) and flux creep rates (<em>S</em>) in β-FeSe single crystals. This analysis was based on magnetization measurements. Additionally, we establish correlations with the recently reported magnetic field-induced geometrical deformation of the vortex lattice, transitioning from hexagonal to square shape due to a rhombic distortion [A. V. Putilov et al. Phys. Rev <strong>99</strong> (2019) 144514]. The results show that the magnetic field dependence of <em>J_c</em> displays distinct regimes, which is reflected by changes in <em>S</em>. The vortex dynamics is analyzed within the framework of the collective creep theory. <em>S</em> is characterized by low pinning energies and glassy exponents according to the expectation for small-bundles at low temperatures and magnetic fields where a hexagonal vortex lattice was reported. Conversely, we observe a systematic increase in <em>S</em>, resembling a shift from small to large vortex bundles, at magnetic fields corresponding to the rhombic distortion. Last, the relaxation rates exhibit significant values for magnetic fields where a square vortex lattice is expected, suggesting a potential crossover from elastic to plastic creep. Our findings highlight a direct relationship between vortex lattice deformations and a decrease in vortex pinning related to vortex-defect interactions.</p></div>","PeriodicalId":20159,"journal":{"name":"Physica C-superconductivity and Its Applications","volume":"618 ","pages":"Article 1354466"},"PeriodicalIF":1.7,"publicationDate":"2024-02-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139830382","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}