Physica C-superconductivity and Its Applications最新文献

{"title":"Magneto-thermal-switching in type-I and type-II superconductors","authors":"M. Yoshida ,&nbsp;H. Arima ,&nbsp;Y. Watanabe ,&nbsp;A. Yamashita ,&nbsp;Y. Mizuguchi","doi":"10.1016/j.physc.2024.1354536","DOIUrl":"https://doi.org/10.1016/j.physc.2024.1354536","url":null,"abstract":"<div><p>Thermal switching by applying magnetic field is one of the key technologies in thermal management in electronic devices. In low-temperature devices, superconductors can be used as a magneto-thermal-switching (MTS) materials due to the large change in carrier thermal conductivity by the superconducting transition. In this study, we measured the temperature (<em>T</em>) and magnetic field (<em>H</em>) dependences of thermal conductivity (<em>κ</em>) of Sn, Ta and V to enrich knowledge on MTS of type-Ⅰ and type-Ⅱ superconductors. From the data analyses, we found different trends of <em>κ</em>-<em>H</em> curves in type-Ⅰ and type-Ⅱ superconductors. The normalized <em>κ</em>-<em>H</em> curves of type-Ⅰ superconductors showed the similar behavior, which is solely governed by <em>H</em>_c. However, the <em>κ</em>-<em>H</em> curves of type-Ⅱ superconductors were affected by the <em>H</em>_c1 and <em>H</em>_c2, and its behavior greatly depends on the materials. In addition, we investigated the elemental composition of Sn and Ta to explore the origin of weak hysteresis in the <em>κ</em>-<em>H</em> curves and revealed the importance of impurity on the hysteresis of <em>κ</em>-<em>H</em> curves.</p></div>","PeriodicalId":20159,"journal":{"name":"Physica C-superconductivity and Its Applications","volume":"623 ","pages":"Article 1354536"},"PeriodicalIF":1.7,"publicationDate":"2024-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141242647","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 new physical reservoir using the complex dynamics of electric fields in type-II superconductors containing pinning centers interacting with quantized magnetic flux lines","authors":"Ken Arita ,&nbsp;Tenma Ueda ,&nbsp;Edmund Soji Otabe ,&nbsp;Yuki Usami ,&nbsp;Hirofumi Tanaka ,&nbsp;Tetsuya Matsuno","doi":"10.1016/j.physc.2024.1354522","DOIUrl":"https://doi.org/10.1016/j.physc.2024.1354522","url":null,"abstract":"<div><p>Reservoir computing, which takes advantage of physical phenomena with nonlinearities, is attracting a lot of attention. Therefore, it is expected to focus on superconductivity, a physical phenomenon with nonlinearities between the output electric field and the input current density. Compared to other physical phenomena used in reservoirs, it is considered that with superconductivity, the nonlinearity can easily be adjusted spatially by pin placement to produce dynamics suitable for reservoirs. The nonlinearity between the electric field generated by the motion of the quantized magnetic flux lines and the input current density was used to perform a reservoir computing task. Three waveform generation tasks, a NARMA2 task and a nonlinear-memory task were performed, and all tasks were generally successful. It was found that the electromagnetic phenomenon in superconductors can be used as a physical reservoir.</p></div>","PeriodicalId":20159,"journal":{"name":"Physica C-superconductivity and Its Applications","volume":"622 ","pages":"Article 1354522"},"PeriodicalIF":1.7,"publicationDate":"2024-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141164176","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":"Topological solitons in charge-6e flux quantized state of Kagome superconductors","authors":"Ling-Feng Zhang ,&nbsp;Zi-Hao Zhou ,&nbsp;Qing Huang","doi":"10.1016/j.physc.2024.1354512","DOIUrl":"https://doi.org/10.1016/j.physc.2024.1354512","url":null,"abstract":"<div><p>A recent Little-Parks experiment on the new Kagome superconductor CsV<span><math><msub><mrow></mrow><mrow><mn>3</mn></mrow></msub></math></span>Sb<span><math><msub><mrow></mrow><mrow><mn>5</mn></mrow></msub></math></span> demonstrated resistance oscillation with a period of <span><math><mrow><msub><mrow><mi>ϕ</mi></mrow><mrow><mn>0</mn></mrow></msub><mo>/</mo><mn>3</mn><mo>=</mo><mi>h</mi><mi>c</mi><mo>/</mo><mn>6</mn><mi>e</mi></mrow></math></span>. This observation of charge-<span><math><mrow><mn>6</mn><mi>e</mi></mrow></math></span> flux quantization is effectively explained by a three-component Ginzburg–Landau (GL) model that incorporates second-order Josephson-type couplings. Here, we numerically solve the GL model to present stable topological solitons. We reveal the structures of these solitons, characterized by closed domain walls with attached vortices. We identify two types of domain walls. These solitons possess multiple flux quanta and exhibit a ringlike geometry. Furthermore, we present the characteristic magnetic field distributions of these solitons, enabling their identification in, e.g., scanning Hall probe and scanning SQUID experiments.</p></div>","PeriodicalId":20159,"journal":{"name":"Physica C-superconductivity and Its Applications","volume":"622 ","pages":"Article 1354512"},"PeriodicalIF":1.7,"publicationDate":"2024-05-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141090471","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":"Describing heat dissipation in the resistive state of three-dimensional superconductors","authors":"Leonardo Rodrigues Cadorim,&nbsp;Lucas Veneziani de Toledo,&nbsp;Edson Sardella","doi":"10.1016/j.physc.2024.1354531","DOIUrl":"https://doi.org/10.1016/j.physc.2024.1354531","url":null,"abstract":"<div><p>In this work we study the role of the heat diffusion equation in simulating the resistive state of superconducting films. By analyzing the current–voltage and current-resistance characteristic curves for temperatures close to <span><math><msub><mrow><mi>T</mi></mrow><mrow><mi>c</mi></mrow></msub></math></span> and various heat removal scenarios, we demonstrate that heat diffusion notably influences the behavior of the resistive state, specially near the transition to the normal state, where heat significantly changes the critical current and the calculated resistance. Furthermore, we show how the efficiency of the substrate has important effects in the dynamics of the system, particularly for lower temperatures. Finally, we investigate the hysteresis loops, the role of the film thickness and of the Ginzburg–Landau parameter, the findings reassuring the significance of accounting for heat diffusion in accurately modeling the resistive state of superconducting films and provide valuable insights into its complex dynamics. To accomplish these findings, we have used the <span><math><mrow><mn>3</mn><mi>D</mi></mrow></math></span> generalized Ginzburg–Landau equation coupled with the heat diffusion equation.</p></div>","PeriodicalId":20159,"journal":{"name":"Physica C-superconductivity and Its Applications","volume":"622 ","pages":"Article 1354531"},"PeriodicalIF":1.7,"publicationDate":"2024-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141084156","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":"MgB2 Josephson Junctions fabricated by Focused Helium Ion Beam with different irradiation doses on SiC and MgO substrates","authors":"Dali Yin ,&nbsp;Xinwei Cai ,&nbsp;Tiequan Xu ,&nbsp;Ruining Sun ,&nbsp;Ziwen Chen ,&nbsp;Ying Han ,&nbsp;Lifeng Tian ,&nbsp;Yue Wang ,&nbsp;Yan Zhang ,&nbsp;Zizhao Gan","doi":"10.1016/j.physc.2024.1354532","DOIUrl":"10.1016/j.physc.2024.1354532","url":null,"abstract":"<div><p>Recently, high quality MgB<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span> single junctions and junction arrays fabricated by Focused Helium Ion Beam irradiation (He-FIB) have been reported. However, the effects of irradiation doses and substrates on junction properties have not been analysed systematically. In this work, 30 nm MgB<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span> thin films were deposited on SiC (0001) and MgO (111) substrates using Hybrid Physical–Chemical Vapour Deposition (HPCVD) technique and then etched into 2–4 <span><math><mrow><mi>μ</mi><mi>m</mi></mrow></math></span> wide microbridges. 2000–6000 ions/nm doses of He-FIB were irradiated across these microbridges, creating narrow junction barriers. <span><math><mi>R</mi></math></span>–<span><math><mi>T</mi></math></span> curves exhibit a clear foot-like structure that enlarges as irradiation dose increases. Temperature dependence of junction properties (critical current <span><math><msub><mrow><mi>I</mi></mrow><mrow><mi>c</mi></mrow></msub></math></span>, junction normal state resistance <span><math><msub><mrow><mi>R</mi></mrow><mrow><mi>n</mi></mrow></msub></math></span>, characteristic voltage <span><math><msub><mrow><mi>V</mi></mrow><mrow><mi>c</mi></mrow></msub></math></span>) shows that all junctions in our experiment exhibit superconductor–normal–superconductor (SNS) like behaviour and higher irradiation doses create thicker junction barriers. Furthermore, we analyse junction properties dependence on irradiation doses which yields an exponential change law. Finally, Fraunhofer diffraction-like patterns and Shapiro steps of junctions are also measured. Our results show MgB<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span> Josephson Junctions with adjustable properties can be fabricated by He-FIB on SiC and MgO substrates, which provides a solid foundation for future application devices research.</p></div>","PeriodicalId":20159,"journal":{"name":"Physica C-superconductivity and Its Applications","volume":"623 ","pages":"Article 1354532"},"PeriodicalIF":1.7,"publicationDate":"2024-05-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141132621","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":"Transverse resistance variations in helically wound 2G ReBCO high-temperature superconducting tape with core under transverse cycling and bending loads","authors":"Yang Liu ,&nbsp;Keyang Wang ,&nbsp;Yuanwen Gao","doi":"10.1016/j.physc.2024.1354534","DOIUrl":"https://doi.org/10.1016/j.physc.2024.1354534","url":null,"abstract":"<div><p>The variations in normalized transverse resistance of 2G HTS tape in a helically wound configuration with the core were measured at room temperature (RT) and 77 K under transverse cyclic and three-point bending loads. The observed experimental phenomena were explained by considering the differences in gap sizes between the superconducting tape and copper core, as well as between the superconducting tapes when multiple tapes are wound during sample preparation and cooling. By analyzing the impact of winding parameters, we offer engineering recommendations to mitigate the increase in transverse resistance and enhance the bearing ability of superconducting tapes under transverse cyclic and three-point bending loads at 77 K. These recommendations include augmenting pre-tension during the winding process, reducing sample placement time before testing, increasing the copper core radius and winding angle, as well as reducing the number of winding tapes.</p></div>","PeriodicalId":20159,"journal":{"name":"Physica C-superconductivity and Its Applications","volume":"622 ","pages":"Article 1354534"},"PeriodicalIF":1.7,"publicationDate":"2024-05-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141078590","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":"Enhancing electric field calculation in HTS tape simulations for currents exceeding the critical limit using full HTS tape modeling","authors":"Gabriel dos Santos ,&nbsp;Bárbara Maria Oliveira Santos","doi":"10.1016/j.physc.2024.1354518","DOIUrl":"https://doi.org/10.1016/j.physc.2024.1354518","url":null,"abstract":"<div><p>Superconducting devices are an interesting technological option for improvement of efficiency of energy systems. High-temperature superconducting tapes are among the best choices for power applications. Because of their high non-linearity, the design of devices with superconducting tape requires specific simulation models and methods to correctly represent the superconducting behavior. The J-A formulation has been investigated as an efficient tool to represent the electromagnetic behavior of such devices. It is based on the current density (J) and magnetic vector potential (A), and able to represent both superconducting materials and ferromagnetic materials. With regards to the tapes, the use of thin-film approximation can be successful with the J-A formulation. Usually, only representations considering the superconducting layer of tapes have been investigated. This becomes a problem for operations where the current in the superconductor surpasses the critical current, for example in transient analysis. This paper presents an analysis of the effects the inclusion of all of the tapes’ layers have on simulations with the J-A formulation with thin-film approximations. By considering all layers of the tape, one represents the transition between superconducting and high-loss states of the tape. A simple system, consisting of a single tape with applied current, has been studied as benchmark and simulated with J-A and the more established T-A formulation in two cases: considering all layers; and only the superconducting layers. Results show that results for the J-A and T-A formulations are compatible and the inclusion of all layers improves the stability of the simulation and provides correct assessment of the electric field in the tapes.</p></div>","PeriodicalId":20159,"journal":{"name":"Physica C-superconductivity and Its Applications","volume":"622 ","pages":"Article 1354518"},"PeriodicalIF":1.7,"publicationDate":"2024-05-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141067880","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 properties of Pd-Heusler rare earth from ab initio and isotropic Eliashberg function","authors":"S. Mouchou ,&nbsp;Y. Toual ,&nbsp;A. Azouaoui ,&nbsp;A. Rezzouk ,&nbsp;K. Bouslykhane ,&nbsp;A. Hourmatallah ,&nbsp;N. Benzakour","doi":"10.1016/j.physc.2024.1354517","DOIUrl":"https://doi.org/10.1016/j.physc.2024.1354517","url":null,"abstract":"<div><p>Ab initio was employed to investigate the structural, electronic, and superconducting properties of the Heusler alloys Pd<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span>TmSn, Pd<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span>YbSn, and Pd<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span>LuSn. The results reveal that these alloys exhibit both structural and dynamic stability in a cubic face-centered lattice. The isotropic Eliashberg function was used to calculate the superconductor properties. The phonon–electron couplings fall within the range characteristic of medium-coupling superconductors. Analysis of the Fermi surfaces identifies the presence of necks connecting the first Brillouin zones, which facilitate electron pairing. The calculated superconducting critical temperatures using the Allen–Dynes equation are in agreement with previous experimental and theoretical findings.</p></div>","PeriodicalId":20159,"journal":{"name":"Physica C-superconductivity and Its Applications","volume":"622 ","pages":"Article 1354517"},"PeriodicalIF":1.7,"publicationDate":"2024-05-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140913869","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":"Investigation of superconductivity of A15 type cubic Nb3Os material by using density functional theory","authors":"Fatih Kurtuluş ,&nbsp;Ertuğrul Karaca ,&nbsp;Sadık Bağcı","doi":"10.1016/j.physc.2024.1354515","DOIUrl":"https://doi.org/10.1016/j.physc.2024.1354515","url":null,"abstract":"<div><p>In this study, the structural, elastic, electronic, phonon and electron-phonon interaction properties of A15 type cubic Nb₃Os compound were investigated by density functional theory. The lattice constant of this compound was obtained in agreement with experiments, and the investigation of elastic properties revealed its ductile nature. From electronic calculations for Nb₃Os, the density of states at Fermi level (N(E_F)) was found to be 5.31 states/eV with the largest contribution of Nb 4d orbitals. According to the results obtained from phonon calculations, Nb₃Os was found to be dynamically stable in the cubic A15 structure and phonon modes were largely formed by the vibrations of Nb atoms. Using the electronic and phonon properties, we determined the Eliashberg spectral function, which illustrates the electron-phonon interaction. The electron-phonon interaction parameter and average phonon frequency values for Nb₃Os were found to be 0.41 and 222.97 K, respectively. The calculated superconducting transition temperature of 1.05 K is in excellent agreement with the experimental value of 1.02 K.</p></div>","PeriodicalId":20159,"journal":{"name":"Physica C-superconductivity and Its Applications","volume":"621 ","pages":"Article 1354515"},"PeriodicalIF":1.7,"publicationDate":"2024-05-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140823127","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 levitation force and stiffness enhancement of single domain GdBCO bulk superconductor by an axial background magnetic field","authors":"Yijin Zhao,&nbsp;Jiaqi Wang,&nbsp;Wanmin Yang,&nbsp;Jing Chen,&nbsp;Jiarui Liu","doi":"10.1016/j.physc.2024.1354516","DOIUrl":"https://doi.org/10.1016/j.physc.2024.1354516","url":null,"abstract":"<div><p>How to improve the levitation force (F_L) and its stiffness between a permanent magnet and a REBCO bulk superconductor is one of the most key and attractive problems to be solved for practical applications. In this paper, we provided a novel hybrid magnet added superconductor system (HMS) to enhance the levitation force and the stiffness, the HMS sample is assembled by a single domain GdBCO bulk with an attached permanent magnet (PM) serving as an axial background magnetic field. The results indicate that (1) the F_L increased first and decreased then with the increase of the PM diameter (d_PM), the largest F_L is achieved when the d_PM approaches the diameter of the GdBCO bulk, F_L has been improved up to 152% with a thinner PM; (2) the F_L increased with the increase of the PM thickness and saturated at a certain value, F_L have been improved up to 168% with a thicker PM; (3) the stiffness of F_L has been improved up to 187% and 201% with the increase of the PM diameter and thickness; (4) the F_L and its stiffness enhancement dependent on the positive trapped field of the field cooled HMS samples. The results are of great significance to improve the performance and stability of maglev systems, the mechanism for enhancing the levitation force and stiffness property has been investigated in details.</p></div>","PeriodicalId":20159,"journal":{"name":"Physica C-superconductivity and Its Applications","volume":"621 ","pages":"Article 1354516"},"PeriodicalIF":1.7,"publicationDate":"2024-05-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140878916","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}