Physica C-superconductivity and Its Applications最新文献

{"title":"Design of superconducting magnets for high energy beam transport lines for proton cancer therapy","authors":"Gang He ,&nbsp;Yi Zhu ,&nbsp;Wenjie Yang ,&nbsp;Yu Liang ,&nbsp;Yiqin Lei ,&nbsp;Yanbing Yang ,&nbsp;Pengshan Chang ,&nbsp;Lizhen Ma ,&nbsp;Guangquan Chen ,&nbsp;Kedong Wang ,&nbsp;Xu Zhang ,&nbsp;Kai Wang ,&nbsp;Tianfa Liao","doi":"10.1016/j.physc.2025.1354718","DOIUrl":"10.1016/j.physc.2025.1354718","url":null,"abstract":"<div><div>In proton cancer therapy, to overcome the size and performance limitations of conventional electromagnetic systems, we have designed a superconducting high-energy beam transport line that utilizes superconducting magnets to provide higher magnetic fields, thereby significantly reducing system size and enhancing efficiency. The transport line consists of six groups of superconducting magnets, each employing a discrete cosine theta (DCT) coil structure <span><span>[1]</span></span>, <span><span>[2]</span></span>, <span><span>[3]</span></span>, <span><span>[4]</span></span>, <span><span>[5]</span></span>, comprising one curved dipole magnet and two quadrupole magnets, forming a Q-D-Q (quadrupole-dipole-quadrupole) configuration. The dipole magnet generates a central field of 2.77 T with a bending radius of 900 mm, while the quadrupole magnets have a gradient of 40 T/m. To ensure magnetic field quality, we developed a parametric model in CST and optimized the field characteristics, achieving an integral magnetic field uniformity of better than 0.01%. During rapid excitation, eddy current losses in metallic structures and AC losses in superconductors lead to temperature rise, which may trigger quenching. To mitigate this, we developed a detailed finite element model (FEM) in ANSYS and optimized the magnet’s cooling structure, ensuring that the maximum temperature rise is limited to 0.66 K over three operating cycles. Simultaneously, we established a 2D structural model to analyze the stresses in the magnet, confirming that the Von Mises stress is lower than the yield stress. Through these optimizations, a prototype was successfully fabricated to explore the manufacturing process of the Q-D-Q magnets. This work not only provides a technical foundation for future mass production but also offers critical technical reserves for the construction of superconducting Gantries.</div></div>","PeriodicalId":20159,"journal":{"name":"Physica C-superconductivity and Its Applications","volume":"635 ","pages":"Article 1354718"},"PeriodicalIF":1.3,"publicationDate":"2025-08-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144588735","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 Pt-Ti thin-film heating method for de-fluxing SFQ circuits in superconducting computers","authors":"Zhichao Chen,&nbsp;Jian Zhou,&nbsp;Lingyun Li,&nbsp;Lixing You","doi":"10.1016/j.physc.2025.1354748","DOIUrl":"10.1016/j.physc.2025.1354748","url":null,"abstract":"<div><div>This paper proposes a Platinum (Pt)-Ti (Titanium) thin-film heating method for de-fluxing Single Flux Quantum (SFQ) circuits, addressing key limitations of conventional hotspot-based approaches, such as non-uniform temperature distribution, low thermal efficiency, and delayed response. A comprehensive analysis and performance evaluation of different heating methods are conducted to investigate the impact of heat methods on Josephson junction (JJ) de-fluxing. Superconducting computers, which use SFQ logic for high-speed operation and ultra-low power consumption, suffer from logical errors caused by trapped magnetic flux in JJs. To de-flux an SFQ circuit after logic errors, the JJs must be heated above the threshold temperature and then cooled in the absence of a magnetic field. Our studies show that heating the JJs to 22 K or above reliably removes trapped flux. Pt thin-film resistive materials, known for their rapid thermal response and controllable diffusion, offer a more efficient solution for de-fluxing and thermal control in SFQ circuits. The thin-film method demonstrates superior performance, achieving a more uniform temperature distribution (standard deviation of 0.02 K), faster thermal response within 1.2 s, and an optimal heating power of 1500 mW with an effective heating duration of 2 s. These results demonstrate a reliable and efficient de-fluxing method, essential for restoring functionality and ensuring logical error recovery in large-scale superconducting computers.</div></div>","PeriodicalId":20159,"journal":{"name":"Physica C-superconductivity and Its Applications","volume":"635 ","pages":"Article 1354748"},"PeriodicalIF":1.3,"publicationDate":"2025-08-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144588737","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 “Thoughts about boosting superconductivity” [Physica C: Superconductivity and its Applications 632 (2025) 1354688]","authors":"Dirk van der Marel","doi":"10.1016/j.physc.2025.1354754","DOIUrl":"10.1016/j.physc.2025.1354754","url":null,"abstract":"","PeriodicalId":20159,"journal":{"name":"Physica C-superconductivity and Its Applications","volume":"635 ","pages":"Article 1354754"},"PeriodicalIF":1.3,"publicationDate":"2025-08-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144587477","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 Hastelloy tape surfaces flattening efficiency via autonomously designed SDP system derived Y2O3 coatings","authors":"Mingyuan Zhao ,&nbsp;Bowan Tao ,&nbsp;Ruipeng Zhao ,&nbsp;Xi Chen ,&nbsp;Zhenzhe Li ,&nbsp;Tian Xie ,&nbsp;Qichen Wang ,&nbsp;Silong Fang ,&nbsp;Ziwen Jin ,&nbsp;Yudong Xia","doi":"10.1016/j.physc.2025.1354744","DOIUrl":"10.1016/j.physc.2025.1354744","url":null,"abstract":"<div><div>The widespread application of second-generation high-temperature superconducting (2G HTS) tapes has elevated demand for surface smoothing of long-length Hastelloy tapes utilizing simple and low-cost strategies. Amorphous Y₂O₃ has been used to flatten the long-length Hastelloy tape surfaces via solution deposition planarization (SDP). In this work, the autonomously designed SDP system is applied to flatten the Hastelloy surface while significantly increasing progress rate. As a result, lifting speed up to 75 m/h, while the root mean square (RMS) roughness on Hastelloy tape surfaces was reduced from 28.13 nm to 0.76 nm over 5 × 5 μm² areas. These are superior to those of the state-of-the-art SDP lifting speeds. Additionally, the surface flattening process was elaborated through power spectral density (PSD). The Hastelloy tape surfaces have been confirmed to form a well-biaxially textured MgO buffer layer. The autonomously designed SDP system shed light on an effective strategy for flattening long-length Hastelloy tape surfaces.</div></div>","PeriodicalId":20159,"journal":{"name":"Physica C-superconductivity and Its Applications","volume":"634 ","pages":"Article 1354744"},"PeriodicalIF":1.3,"publicationDate":"2025-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144194698","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":"Analysis of the suspension current of a magnetically levitated superconducting rotor structure","authors":"Xian Yi ,&nbsp;Chunyan Cui ,&nbsp;Xinning Hu ,&nbsp;Yuan Zhang ,&nbsp;Xu Cui ,&nbsp;Hao Li ,&nbsp;Qiuliang Wang ,&nbsp;Quansheng Sun","doi":"10.1016/j.physc.2025.1354730","DOIUrl":"10.1016/j.physc.2025.1354730","url":null,"abstract":"<div><div>The high precision of the superconducting magnetic levitation device relies on the rotor's high-speed rotation and disturbance resistance. In actual work, the appropriate support current is conducive to realizing the high-speed driving of the superconductor rotor and improving its anti-disturbance ability. A comprehensive analysis of suspension current characteristics in superconducting magnetic levitation systems is therefore essential. This study analyzes the suspension current characteristics in superconducting magnetic levitation systems. The structure is first introduced, followed by a finite element model based on the vector magnetic potential equation to investigate electromagnetic relationships. A suspension current adjustment method is then proposed and validated through experimental tests. In conclusion, an analysis was conducted to determine the influence law of the change in suspension current on the drift speed. This analysis was based on the change in interference torque caused by the change in suspension current. The results establish a framework for optimizing suspension current adjustment and serve as a benchmark for improving device accuracy.</div></div>","PeriodicalId":20159,"journal":{"name":"Physica C-superconductivity and Its Applications","volume":"634 ","pages":"Article 1354730"},"PeriodicalIF":1.3,"publicationDate":"2025-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144194697","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 chemical etching of copper stabilization layer on the performance and microstructure of REBa2Cu3O7-x coated conductors","authors":"Ziming Wang ,&nbsp;Hao Liang ,&nbsp;Zhenchuang Zhang ,&nbsp;Xintao Zhang ,&nbsp;Shuowei Gao ,&nbsp;Han Yang ,&nbsp;Zhan Zhang ,&nbsp;Huan Jin ,&nbsp;Chao Zhou ,&nbsp;Jinggang Qin ,&nbsp;Huajun Liu ,&nbsp;Fang Liu","doi":"10.1016/j.physc.2025.1354715","DOIUrl":"10.1016/j.physc.2025.1354715","url":null,"abstract":"<div><div>The etching of metallic layers is a critical step in the preparation of superconducting joints and in the study of the degradation mechanism of the superconducting performance of REBa₂Cu₃O_7-x (REBCO) coated conductors (CCs). The copper stabilization layer and the silver cap layer need to be completely removed from the specified area and retain excellent superconductivity and microstructure. Since REBCO CCs are sensitive to most inorganic solutions, the etching conditions can severely affect the performance and microstructure when using a wet etching process. We have systematically investigated the effects of ferric chloride (FeCl₃) solutions on the crystal structure, microscopic morphology, critical current (<em>I</em>_c) and <em>n</em>-values of REBCO CCs when etching copper stabilization layers, and have obtained etching parameters that hardly degrade <em>I</em>_c of CCs. However, when the etching conditions were varied, we found a significant degradation of <em>I</em>_c and investigated the underlying causes of this degradation. Scanning electron microscopy (SEM), Raman spectroscopy and X-ray diffraction (XRD) analyses showed that the main cause of the superconducting performance degradation is the delamination of the superconducting layer and the increase of oxygen defects in the lattice.</div></div>","PeriodicalId":20159,"journal":{"name":"Physica C-superconductivity and Its Applications","volume":"634 ","pages":"Article 1354715"},"PeriodicalIF":1.3,"publicationDate":"2025-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144194764","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 analysis of cold mass support system for superconducting magnets without transport protection","authors":"Zuda Fan ,&nbsp;Ce Xu ,&nbsp;Wei Zou ,&nbsp;Hui Wang ,&nbsp;Yichuan Zheng ,&nbsp;Shunzhong Chen ,&nbsp;Junsheng Cheng ,&nbsp;Qiuliang Wang","doi":"10.1016/j.physc.2025.1354700","DOIUrl":"10.1016/j.physc.2025.1354700","url":null,"abstract":"<div><div>For the superconducting magnets that require high environmental adaptability during unprotected long-distance transportation, the cold mass support structure must have sufficient rigidity to minimize the variation of coaxiality between the cold mass and the warm bore after transportation. Based on the T700 carbon fiber reinforced plastic (CFRP) with low thermal conductivity and high mechanical strength, a three-dimensional adjustable cold mass support structure is constructed. To monitor the tension forces of the rods and the displacement of the cold mass, the tension sensors and the displacement sensors are integrated into this structure. The support structure is analysed for conductive heat leak, structural strength and stability under vibration. The effects of highway transportation on the displacement of the cold mass and the stress of the rods are studied by vibration experiment. Additionally, the situation of the cold mass may still change under the long-term accumulation of transportation. An adjustment method of the displacement is proposed to solve this problem. The result shows that the displacement of the cold mass is less than 0.01 mm after the vibration experiment. The coaxiality error can be adjusted within 0.1 mm. The rods can support the stress during vibration. The design of the support structure is reasonable and reliable.</div></div>","PeriodicalId":20159,"journal":{"name":"Physica C-superconductivity and Its Applications","volume":"634 ","pages":"Article 1354700"},"PeriodicalIF":1.3,"publicationDate":"2025-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144194760","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":"Influence of growth parameters on the superconducting transition temperature in granular aluminum films","authors":"Aniruddha Deshpande,&nbsp;Jan Pusskeiler,&nbsp;Christian Prange,&nbsp;Uwe Rogge,&nbsp;Martin Dressel,&nbsp;Marc Scheffler","doi":"10.1016/j.physc.2025.1354709","DOIUrl":"10.1016/j.physc.2025.1354709","url":null,"abstract":"<div><div>This study investigates the influence of various growth parameters on normal-state resistivity and superconducting transition temperature <span><math><msub><mrow><mi>T</mi></mrow><mrow><mi>c</mi></mrow></msub></math></span> of granular aluminum films. Specifically, we focus on the effects of oxygen flow and aluminum evaporation rate during the growth process conducted at different substrate temperatures, from 300 K down to 25 K. We report systematic correlations between the growth conditions, the normal-state resistivity, and <span><math><msub><mrow><mi>T</mi></mrow><mrow><mi>c</mi></mrow></msub></math></span>. Furthermore, our findings provide insights into optimizing the superconducting characteristics of granular aluminum.</div></div>","PeriodicalId":20159,"journal":{"name":"Physica C-superconductivity and Its Applications","volume":"634 ","pages":"Article 1354709"},"PeriodicalIF":1.3,"publicationDate":"2025-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143923238","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":"Critical current density properties of thick YBa2Cu3Oy films with different thicknesses","authors":"S. Ito ,&nbsp;M. Kiuchi ,&nbsp;T. Horide ,&nbsp;Y. Yoshida","doi":"10.1016/j.physc.2025.1354734","DOIUrl":"10.1016/j.physc.2025.1354734","url":null,"abstract":"<div><div>Even in REBa₂Cu₃O<em>_y</em> (REBCO) films, which exhibit high critical current density (<em>J</em>_c) under low-temperature and high-magnetic-field conditions, their performance deteriorates significantly at high-temperatures because of pronounced flux creep induced by thermal agitation. This degradation is particularly pronounced in thin superconducting films, as the thickness constrains the pinning correlation length. In this study, we examined the effect of YBCO film thickness on <em>J</em>_c within the range of 0.94 to 3.7 μm. While some variations were observed depending on crystal orientation, thicker superconducting layers demonstrated a smaller reduction in <em>J</em>_c with increasing magnetic field in high-temperature regions, resulting in superior <em>J</em>_c values under high-temperature and high-magnetic-field conditions. Moreover, the apparent pinning potential <span><math><msubsup><mi>U</mi><mn>0</mn><mo>*</mo></msubsup></math></span>, determined from magnetization relaxation measurements, was larger for thicker films in these conditions, indicating that <span><math><msubsup><mi>U</mi><mn>0</mn><mo>*</mo></msubsup></math></span> is influenced by the thickness of the superconducting layer. These findings are further supported by the flux creep flow model analysis. Collectively, these results suggest that not only introducing strong pinning forces but also increasing the thickness of the superconducting layer is an effective strategy for enhancing performance near liquid nitrogen temperatures.</div></div>","PeriodicalId":20159,"journal":{"name":"Physica C-superconductivity and Its Applications","volume":"634 ","pages":"Article 1354734"},"PeriodicalIF":1.3,"publicationDate":"2025-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143937472","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":"Delamination behaviour of the meter‐long class Fe(Se,Te) coated conductor tapes","authors":"Han Yang ,&nbsp;Fang Liu ,&nbsp;Hongjun Ma ,&nbsp;Zhenchuang Zhang ,&nbsp;Xiao Liu ,&nbsp;Shu Tao ,&nbsp;Ziming Wang ,&nbsp;Huan Jin ,&nbsp;Jinggang Qin ,&nbsp;Huajun Liu ,&nbsp;Chao Zhou","doi":"10.1016/j.physc.2025.1354728","DOIUrl":"10.1016/j.physc.2025.1354728","url":null,"abstract":"<div><div>FeSeTe coated conductor (CC) tapes have garnered significant attention due to their simple crystal structure, straightforward preparation process, elimination of the need for heat treatment, and the absence of the toxic element arsenic (As). The material's development is progressing favorably, with the successful production of meter-long class tapes. To facilitate its broader application, this study investigates the transverse delamination strength of FeSeTe CC tapes, with a particular focus on the impact of temperature and the location of delamination occurrences. The mechanical delamination tests were conducted using the anvil method, while the microstructure of the fracture surfaces was analyzed using transmission electron microscopy (TEM). The results indicate that the average transverse delamination strength of copper electroplated tapes at room temperature (RT) is 1.77 MPa, which decreases significantly to 0.74 MPa at 77 K, highlighting the substantial impact of low temperature on the mechanical properties of the tapes. TEM analysis revealed that most delamination occurs at the superconductor layer. These findings provide valuable insights for optimizing the mechanical performance of FeSeTe CC tapes for practical applications.</div></div>","PeriodicalId":20159,"journal":{"name":"Physica C-superconductivity and Its Applications","volume":"634 ","pages":"Article 1354728"},"PeriodicalIF":1.3,"publicationDate":"2025-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144194696","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}