MgB2 superconducting wires made with internal magnesium diffusion (IMD) process have reached an excellent performance than other routes. However, the incomplete Mg/B reaction has been the core problem of IMD process. In this study, MgB2/Ni IMD superconducting monofilament wires were prepared using the improved IMD process. By exploring annealing processes during fabrication, we improved the ductility of the wires and ensured the uniform continuity of the central Mg core filaments. The optimal heat treatment process for MgB2/Ni IMD wires was ascertained by micro structural morphology analysis, phase structure analysis, superconducting property analysis. The study demonstrates that this processing technique leads to a more complete reaction between Mg and B after heat treatment. The critical current density of MgB2/Ni super-conducting wires was measured at 4.2 K, demonstrating high current-carrying capabilities, particularly at high magnetic fields. This research provides valuable insights for the processing and heat treatment of MgB2/Ni multi-core superconducting wires in the future.
{"title":"Preparation and Properties of High Performance MgB2/Ni Superconducting Wire With Improved Internal Magnesium Diffusion Process","authors":"Yiming Wang;Qingyang Wang;Zhenyu Chen;Dan Xi;Hongli Hou;Shengnan Zhang;Jianqing Feng;Jianfeng Li;Pingxiang Zhang","doi":"10.1109/TASC.2026.3654478","DOIUrl":"https://doi.org/10.1109/TASC.2026.3654478","url":null,"abstract":"MgB<sub>2</sub> superconducting wires made with internal magnesium diffusion (IMD) process have reached an excellent performance than other routes. However, the incomplete Mg/B reaction has been the core problem of IMD process. In this study, MgB<sub>2</sub>/Ni IMD superconducting monofilament wires were prepared using the improved IMD process. By exploring annealing processes during fabrication, we improved the ductility of the wires and ensured the uniform continuity of the central Mg core filaments. The optimal heat treatment process for MgB<sub>2</sub>/Ni IMD wires was ascertained by micro structural morphology analysis, phase structure analysis, superconducting property analysis. The study demonstrates that this processing technique leads to a more complete reaction between Mg and B after heat treatment. The critical current density of MgB<sub>2</sub>/Ni super-conducting wires was measured at 4.2 K, demonstrating high current-carrying capabilities, particularly at high magnetic fields. This research provides valuable insights for the processing and heat treatment of MgB<sub>2</sub>/Ni multi-core superconducting wires in the future.","PeriodicalId":13104,"journal":{"name":"IEEE Transactions on Applied Superconductivity","volume":"36 5","pages":"1-4"},"PeriodicalIF":1.8,"publicationDate":"2026-01-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146026427","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}
Pub Date : 2026-01-16DOI: 10.1109/TASC.2026.3655165
Avirup Roy;Robinjeet Singh;Joel C. Weber;William B. Doriese;Johnathon Gard;Mark W. Keller;John A. B. Mates;Kelsey M. Morgan;Nathan J. Ortiz;Daniel S. Swetz;Daniel R. Schmidt;Joel N. Ullom;Evan P. Jahrman;Thomas C. Allison;Sasawat Jamnuch;John Vinson;Charles J. Titus;Cherno Jaye;Daniel A. Fischer;Galen C. O’Neil
We present the electrothermal characterization of transition-edge sensor (TES) detectors suspended on Si membranes fabricated using a silicon-on-insulator wafer. The use of an all-silicon fabrication platform, in contrast to the more commonly used silicon nitride membranes, is compatible with monolithic fabrication of integrated TES and SQUID circuits. The all-silicon architecture additionally allows the efficient use of focal plane area; the readout circuitry may be positioned out of the focal plane by bending a thinned portion of the chip. Compatibility with integrated fabrication and the efficient use of focal plane area provide a path to an efficient soft X-ray spectrometer. This work is motivated by our goal to develop a 10 000-pixel TES spectrometer to overcome critical measurement limitations in catalysis research. The characterization of fragile, carbon-based intermediates via techniques, such as resonant inelastic X-ray scattering (RIXS), is often precluded by the slow, high-flux nature of existing technologies. The new instrument will allow for fast RIXS measurements to be made without causing sample damage. We verify the detector models and measure the energy resolution using a pulsed optical laser, demonstrating the viability of this approach for the final instrument to be deployed at the National Synchrotron Light Source II.
{"title":"Characterization of Silicon-Membrane TES Microcalorimeters for Large-Format X-Ray Spectrometers With Integrated Microwave SQUID Readout","authors":"Avirup Roy;Robinjeet Singh;Joel C. Weber;William B. Doriese;Johnathon Gard;Mark W. Keller;John A. B. Mates;Kelsey M. Morgan;Nathan J. Ortiz;Daniel S. Swetz;Daniel R. Schmidt;Joel N. Ullom;Evan P. Jahrman;Thomas C. Allison;Sasawat Jamnuch;John Vinson;Charles J. Titus;Cherno Jaye;Daniel A. Fischer;Galen C. O’Neil","doi":"10.1109/TASC.2026.3655165","DOIUrl":"https://doi.org/10.1109/TASC.2026.3655165","url":null,"abstract":"We present the electrothermal characterization of transition-edge sensor (TES) detectors suspended on Si membranes fabricated using a silicon-on-insulator wafer. The use of an all-silicon fabrication platform, in contrast to the more commonly used silicon nitride membranes, is compatible with monolithic fabrication of integrated TES and SQUID circuits. The all-silicon architecture additionally allows the efficient use of focal plane area; the readout circuitry may be positioned out of the focal plane by bending a thinned portion of the chip. Compatibility with integrated fabrication and the efficient use of focal plane area provide a path to an efficient soft X-ray spectrometer. This work is motivated by our goal to develop a 10 000-pixel TES spectrometer to overcome critical measurement limitations in catalysis research. The characterization of fragile, carbon-based intermediates via techniques, such as resonant inelastic X-ray scattering (RIXS), is often precluded by the slow, high-flux nature of existing technologies. The new instrument will allow for fast RIXS measurements to be made without causing sample damage. We verify the detector models and measure the energy resolution using a pulsed optical laser, demonstrating the viability of this approach for the final instrument to be deployed at the National Synchrotron Light Source II.","PeriodicalId":13104,"journal":{"name":"IEEE Transactions on Applied Superconductivity","volume":"36 6","pages":"1-8"},"PeriodicalIF":1.8,"publicationDate":"2026-01-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146175927","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}
Pub Date : 2026-01-14DOI: 10.1109/TASC.2025.3650523
Dai Oikawa;Hirokazu Komatsu;Keita Tsuzuki;Hiroya Andoh
The configuration of a robust, high-security system has become increasingly important because, as computer processing speeds continue to improve, the vulnerabilities of cryptographic systems that rely on conventional pseudo-random-numbers have raised concerns regarding potential leaks of confidential information. To establish such a secure system, high-quality and high-speed random numbers are essential. Here, high-quality random-numbers are defined as statistically unbiased, non-reproducible, and unpredictable values. One approach to generating such numbers is to exploit physical random phenomena, such as chaos. In particular, chaos in Josephson junctions (JJs) under radio-frequency (RF) irradiation has been identified as a suitable mechanism for random-number generation. In this study, we considered RF-biased intrinsic Josephson junctions (IJJs) in a mesa-type Bi $_{2}$ Sr$_{2}$CaCu $_{2}$ O$_{8+delta }$ single crystal. Since the interactions among stacked IJJs must be considered, it is insufficient to evaluate their properties using the conventional resistively and capacitively shunted junction (RCSJ) circuit model. Instead, we numerically investigated the chaotic voltage of an IJJ stack irradiated with higher frequencies than those typically used in conventional RF systems, employing the capacitively coupled JJ model with diffusion current, which incorporates interlayer interactions. Based on the time-series output voltage of the IJJ, we then generated random-numbers and evaluated their quality using statistical tests.
{"title":"Random-Number Generation Using Chaos in RF-Irradiated Stacked Intrinsic Josephson Junction","authors":"Dai Oikawa;Hirokazu Komatsu;Keita Tsuzuki;Hiroya Andoh","doi":"10.1109/TASC.2025.3650523","DOIUrl":"https://doi.org/10.1109/TASC.2025.3650523","url":null,"abstract":"The configuration of a robust, high-security system has become increasingly important because, as computer processing speeds continue to improve, the vulnerabilities of cryptographic systems that rely on conventional pseudo-random-numbers have raised concerns regarding potential leaks of confidential information. To establish such a secure system, high-quality and high-speed random numbers are essential. Here, high-quality random-numbers are defined as statistically unbiased, non-reproducible, and unpredictable values. One approach to generating such numbers is to exploit physical random phenomena, such as chaos. In particular, chaos in Josephson junctions (JJs) under radio-frequency (RF) irradiation has been identified as a suitable mechanism for random-number generation. In this study, we considered RF-biased intrinsic Josephson junctions (IJJs) in a mesa-type Bi <inline-formula><tex-math>$_{2}$</tex-math></inline-formula> Sr<inline-formula><tex-math>$_{2}$</tex-math></inline-formula>CaCu <inline-formula><tex-math>$_{2}$</tex-math></inline-formula> O<inline-formula><tex-math>$_{8+delta }$</tex-math></inline-formula> single crystal. Since the interactions among stacked IJJs must be considered, it is insufficient to evaluate their properties using the conventional resistively and capacitively shunted junction (RCSJ) circuit model. Instead, we numerically investigated the chaotic voltage of an IJJ stack irradiated with higher frequencies than those typically used in conventional RF systems, employing the capacitively coupled JJ model with diffusion current, which incorporates interlayer interactions. Based on the time-series output voltage of the IJJ, we then generated random-numbers and evaluated their quality using statistical tests.","PeriodicalId":13104,"journal":{"name":"IEEE Transactions on Applied Superconductivity","volume":"36 5","pages":"1-5"},"PeriodicalIF":1.8,"publicationDate":"2026-01-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145982231","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}
Optimizing various fabrication parameters is one of the major challenges in the development of superconducting wires, often resulting in prolonged transition periods from fundamental research to practical applications. Additionally, escalating costs for essential resources such as liquid helium have amplified the difficulty of experimental work, further underscoring the importance of data-driven research approaches. In this study, we focus on magnesium diboride (MgB2) wires and demonstrate the effectiveness of Bayesian optimization in efficiently searching complex parameter spaces to identify optimal fabrication conditions. Specifically, we investigate the internal magnesium diffusion (IMD) process, employing Bayesian optimization and the BOXVIA visualization tool to explore key heat-treatment parameters—namely, heat-treatment time and temperature—with the aim of maximizing the engineering critical current density ($J_{mathrm{e}}$). Our results show that, under conventional conditions, the highest Je was achieved at approximately 700 °C with a short holding time of less than one hour. Moreover, our process informatics approach enabled the discovery of optimal conditions even under unconventional parameter settings. This methodology substantially reduces the number of experimental iterations required and enhances the performance of superconducting wires. Overall, our data-driven optimization strategy offers a promising route for faster, more efficient wire fabrication and the accelerated commercialization of superconducting technologies.
{"title":"Development of Premix Internal-Magnesium-Diffusion MgB2 Wire Using a Data-Driven Approach","authors":"Akiyoshi Matsumoto;Akimitsu Ishii;Rei Kawasaki;Takahiro Hosokawa;Akiyasu Yamamoto","doi":"10.1109/TASC.2026.3652546","DOIUrl":"https://doi.org/10.1109/TASC.2026.3652546","url":null,"abstract":"Optimizing various fabrication parameters is one of the major challenges in the development of superconducting wires, often resulting in prolonged transition periods from fundamental research to practical applications. Additionally, escalating costs for essential resources such as liquid helium have amplified the difficulty of experimental work, further underscoring the importance of data-driven research approaches. In this study, we focus on magnesium diboride (MgB<sub>2</sub>) wires and demonstrate the effectiveness of Bayesian optimization in efficiently searching complex parameter spaces to identify optimal fabrication conditions. Specifically, we investigate the internal magnesium diffusion (IMD) process, employing Bayesian optimization and the BOXVIA visualization tool to explore key heat-treatment parameters—namely, heat-treatment time and temperature—with the aim of maximizing the engineering critical current density (<inline-formula><tex-math>$J_{mathrm{e}}$</tex-math></inline-formula>). Our results show that, under conventional conditions, the highest Je was achieved at approximately 700 °C with a short holding time of less than one hour. Moreover, our process informatics approach enabled the discovery of optimal conditions even under unconventional parameter settings. This methodology substantially reduces the number of experimental iterations required and enhances the performance of superconducting wires. Overall, our data-driven optimization strategy offers a promising route for faster, more efficient wire fabrication and the accelerated commercialization of superconducting technologies.","PeriodicalId":13104,"journal":{"name":"IEEE Transactions on Applied Superconductivity","volume":"36 5","pages":"1-4"},"PeriodicalIF":1.8,"publicationDate":"2026-01-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146026356","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}
As the only high-temperature superconducting material that can be prepared into isotropic round wires, Bi-2212 has important application value in the high magnetic field domain. This study investigates the manufacturing process of connection joints between a Bi-2212 round wire and other superconducting materials. First, pure tin is used to dissolve the sheath materials of the outer layers of each superconducting material, and then the superconducting solder PbBi alloy is used to replace the nonsuperconducting tin. During this process, the influence of time on the dissolution of different metal sheath by the solder was compared and analyzed, and the more appropriate soldering temperature and time are preliminarily given. Second, joints between Bi-2212 and NbTi, Nb3Sn, as well as Bi-2223 were successfully prepared by applying this process, and the current-carrying capacity test was carried out at 4.2 K and 0–1.2 T. Finally, elemental analysis of the joints was performed by using a scanning electron microscope (SEM), confirming the good bonding performance between the PbBi alloy and the base metal.
{"title":"Research on Solder Joints Process between Bi-2212 Round Wire and Other Superconducting Materials","authors":"Lei Yu;Zhen Fang;Qingbin Hao;Hang Zhao;Zhipeng Jiang;Jianyuan Xu;Hangwei Ding;Yuyang Shi;Pengcheng Huang;Zhiyou Chen;Wenge Chen","doi":"10.1109/TASC.2026.3653561","DOIUrl":"https://doi.org/10.1109/TASC.2026.3653561","url":null,"abstract":"As the only high-temperature superconducting material that can be prepared into isotropic round wires, Bi-2212 has important application value in the high magnetic field domain. This study investigates the manufacturing process of connection joints between a Bi-2212 round wire and other superconducting materials. First, pure tin is used to dissolve the sheath materials of the outer layers of each superconducting material, and then the superconducting solder PbBi alloy is used to replace the nonsuperconducting tin. During this process, the influence of time on the dissolution of different metal sheath by the solder was compared and analyzed, and the more appropriate soldering temperature and time are preliminarily given. Second, joints between Bi-2212 and NbTi, Nb<sub>3</sub>Sn, as well as Bi-2223 were successfully prepared by applying this process, and the current-carrying capacity test was carried out at 4.2 K and 0–1.2 T. Finally, elemental analysis of the joints was performed by using a scanning electron microscope (SEM), confirming the good bonding performance between the PbBi alloy and the base metal.","PeriodicalId":13104,"journal":{"name":"IEEE Transactions on Applied Superconductivity","volume":"36 2","pages":"1-6"},"PeriodicalIF":1.8,"publicationDate":"2026-01-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146026618","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}
Pub Date : 2026-01-14DOI: 10.1109/TASC.2026.3654036
Shumin Yu;Guofeng Zhang;Haiyang Mao;Jun Wu;Jiawei Luo;Yongliang Wang;Longqing Qiu;Liangliang Rong
This article reports the wafer-scale fabrication of dc superconducting quantum interference devices (dc-SQUIDs) on 4-in silicon wafers, employing a submicron Josephson junction cross-line process that integrates i-line stepper lithography, in situ trilayer deposition, and a self-aligned insulating layer. Using a stratified regional sampling strategy, 10 SQUIDs are selected from each of the center, transition, and edge regions of the wafer (achieving a total coverage of 49.2%), and the spatial uniformity of key parameters such as critical current, voltage swing, and system flux noise is systematically evaluated. The test results show that the critical currents for the central, transition, and edge regions are (25.4±1.77) μA, (22.4±2.13) μA, and (16.2±2.81) μA, respectively; their corresponding voltage swings are (275±5.95) μV, (255±17.8) μV, and (146±44.7) μV, respectively; and the system flux noises are (1.74±0.131) μΦ0/√Hz, (1.97±0.0880) μΦ0/√Hz, and (2.70±0.452) μΦ0/√Hz, respectively. Statistical analysis shows that from the center to the edge, the critical current and voltage swing demonstrate a downward trend, whereas the system flux noise shows a trend of deterioration. The standard deviation of these parameters gradually increases from the center to the edge, which indicates poorer parameter consistency and more pronounced fluctuations in the region. Further analysis of the coefficient of variation (CV) shows that the CVs of key parameters in the central and transition regions are all below 10%. This verifies that the process route, particularly in these central and transition regions, possesses excellent spatial uniformity, providing a crucial process foundation and data support for the large-scale manufacturing of high-performance SQUIDs.
{"title":"Wafer-Scale Fabrication and Spatial Uniformity Evaluation of SQUIDs With Submicron Josephson Junctions","authors":"Shumin Yu;Guofeng Zhang;Haiyang Mao;Jun Wu;Jiawei Luo;Yongliang Wang;Longqing Qiu;Liangliang Rong","doi":"10.1109/TASC.2026.3654036","DOIUrl":"https://doi.org/10.1109/TASC.2026.3654036","url":null,"abstract":"This article reports the wafer-scale fabrication of dc superconducting quantum interference devices (dc-SQUIDs) on 4-in silicon wafers, employing a submicron Josephson junction cross-line process that integrates i-line stepper lithography, in situ trilayer deposition, and a self-aligned insulating layer. Using a stratified regional sampling strategy, 10 SQUIDs are selected from each of the center, transition, and edge regions of the wafer (achieving a total coverage of 49.2%), and the spatial uniformity of key parameters such as critical current, voltage swing, and system flux noise is systematically evaluated. The test results show that the critical currents for the central, transition, and edge regions are (25.4±1.77) μA, (22.4±2.13) μA, and (16.2±2.81) μA, respectively; their corresponding voltage swings are (275±5.95) μV, (255±17.8) μV, and (146±44.7) μV, respectively; and the system flux noises are (1.74±0.131) μΦ<sub>0</sub>/√Hz, (1.97±0.0880) μΦ<sub>0</sub>/√Hz, and (2.70±0.452) μΦ<sub>0</sub>/√Hz, respectively. Statistical analysis shows that from the center to the edge, the critical current and voltage swing demonstrate a downward trend, whereas the system flux noise shows a trend of deterioration. The standard deviation of these parameters gradually increases from the center to the edge, which indicates poorer parameter consistency and more pronounced fluctuations in the region. Further analysis of the coefficient of variation (CV) shows that the CVs of key parameters in the central and transition regions are all below 10%. This verifies that the process route, particularly in these central and transition regions, possesses excellent spatial uniformity, providing a crucial process foundation and data support for the large-scale manufacturing of high-performance SQUIDs.","PeriodicalId":13104,"journal":{"name":"IEEE Transactions on Applied Superconductivity","volume":"36 2","pages":"1-8"},"PeriodicalIF":1.8,"publicationDate":"2026-01-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146175902","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}
High Temperature Superconducting (HTS) cables developed for superconducting powertrains for electric aircrafts have to demonstrate their robustness, especially towards electric arcs. We propose here a methodology to evaluate HTS cable vulnerability to serial arcs following a quench. First, the arc voltage threshold of an HTS tape is measured under cryogenic temperatures. Then, a model is proposed to predict the peak of the transient voltage developed at the breaking point in case one of the HTS tapes in the cable is broken. This model depends on self and mutual inductances and on current variation dI/dt. A good correlation is obtained between the model and experiments using a simplified setup at room temperature. The comparison between the predicted transient voltage induced in representative HTS cables when one tape is broken with the arc voltage threshold will allow to assess the arcing risk in specific topologies of HTS cable.
{"title":"Serial Arc Risk Analysis in HTS Tapes for Electric Aircraft","authors":"Cécile Weulersse;Jean Rivenc;Ivan Revel;Pedro Barusco;Emelie Nilsson","doi":"10.1109/TASC.2026.3652114","DOIUrl":"https://doi.org/10.1109/TASC.2026.3652114","url":null,"abstract":"High Temperature Superconducting (HTS) cables developed for superconducting powertrains for electric aircrafts have to demonstrate their robustness, especially towards electric arcs. We propose here a methodology to evaluate HTS cable vulnerability to serial arcs following a quench. First, the arc voltage threshold of an HTS tape is measured under cryogenic temperatures. Then, a model is proposed to predict the peak of the transient voltage developed at the breaking point in case one of the HTS tapes in the cable is broken. This model depends on self and mutual inductances and on current variation <italic>dI/dt</i>. A good correlation is obtained between the model and experiments using a simplified setup at room temperature. The comparison between the predicted transient voltage induced in representative HTS cables when one tape is broken with the arc voltage threshold will allow to assess the arcing risk in specific topologies of HTS cable.","PeriodicalId":13104,"journal":{"name":"IEEE Transactions on Applied Superconductivity","volume":"36 5","pages":"1-5"},"PeriodicalIF":1.8,"publicationDate":"2026-01-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146026461","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}
Superconducting transition-edge sensors (TESs) with high sensitivity can detect electromagnetic wave radiations from millimeter/submillimeter, optical to x/γ rays, and have been successfully used in many fields. To improve detection efficiency and sensitivity, large-scale TES arrays are required in combination with multiplexing readout electronics. Compared to other multiplexing schemes, microwave SQUID multiplexing (μMUX), consisting of high-quality microwave superconducting resonators and RF SQUIDs, is most suitable since it provides a wider bandwidth (GHz) and consequently higher multiplexing factor. We designed two types of circuits with different mutual inductances (${{M}_{mathrm{T}}}$) between the resonator and the RF SQUID: 2.3 pH for the weak-coupling channel and 6.5 pH for the strong-coupling channel. The resonator and RF SQUID washers made of 150 nm Nb are first fabricated by magnetron-sputtering and reactive ion etching, followed by the deposition of Nb/Al–AlOx/Nb trilayer and definition of the Josephson junctions of the RF SQUIDs. This work presents a μMUX demonstration chip with five channels with ${{Q}_{mathrm{l}}}$ values of 787 and 3626, and the measured frequency shifts ($Delta {{f}_{text{pp}}}$) of ∼500 kHz and 4 MHz for the weak- coupling and strong-coupling channels, respectively. The open-loop equivalent noise current, obtained from the measured phase noise and resonator responsivity, is $sim 80text{pA}/sqrt {text{Hz}} $ with the strong-coupling channel.
{"title":"Development of Microwave SQUID Multiplexer for Readout of Transition-Edge Sensor Array","authors":"Zhi-Fa Feng;Xian-Feng Zhou;Wen Zhang;Zheng Wang;Qing-Xiao Ma;Pei-Zhan Li;Jia-Qiang Zhong;Wei Miao;Yuan Ren;Qi-Jun Yao;Valery Koshelets;Lyudmila Filippenko;Michael Fominsky;Jing Li;Sheng-Cai Shi","doi":"10.1109/TASC.2026.3653239","DOIUrl":"https://doi.org/10.1109/TASC.2026.3653239","url":null,"abstract":"Superconducting transition-edge sensors (TESs) with high sensitivity can detect electromagnetic wave radiations from millimeter/submillimeter, optical to x/γ rays, and have been successfully used in many fields. To improve detection efficiency and sensitivity, large-scale TES arrays are required in combination with multiplexing readout electronics. Compared to other multiplexing schemes, microwave SQUID multiplexing (<italic>μ</i>MUX), consisting of high-quality microwave superconducting resonators and RF SQUIDs, is most suitable since it provides a wider bandwidth (GHz) and consequently higher multiplexing factor. We designed two types of circuits with different mutual inductances (<inline-formula><tex-math>${{M}_{mathrm{T}}}$</tex-math></inline-formula>) between the resonator and the RF SQUID: 2.3 pH for the weak-coupling channel and 6.5 pH for the strong-coupling channel. The resonator and RF SQUID washers made of 150 nm Nb are first fabricated by magnetron-sputtering and reactive ion etching, followed by the deposition of Nb/Al–AlOx/Nb trilayer and definition of the Josephson junctions of the RF SQUIDs. This work presents a <italic>μ</i>MUX demonstration chip with five channels with <inline-formula><tex-math>${{Q}_{mathrm{l}}}$</tex-math></inline-formula> values of 787 and 3626, and the measured frequency shifts (<inline-formula><tex-math>$Delta {{f}_{text{pp}}}$</tex-math></inline-formula>) of ∼500 kHz and 4 MHz for the weak- coupling and strong-coupling channels, respectively. The open-loop equivalent noise current, obtained from the measured phase noise and resonator responsivity, is <inline-formula><tex-math>$sim 80text{pA}/sqrt {text{Hz}} $</tex-math></inline-formula> with the strong-coupling channel.","PeriodicalId":13104,"journal":{"name":"IEEE Transactions on Applied Superconductivity","volume":"36 6","pages":"1-6"},"PeriodicalIF":1.8,"publicationDate":"2026-01-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146057618","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}
This study explores ternary Ag-added InSn solders to develop low-resistance, reliable, and mechanically robust joints between YBCO tapes, an essential requirement for superconducting magnets, including the magnets in the fusion industry. To investigate the impact of Ag addition to the widely used SnIn solder, several solders were made by adding small amounts of Ag (1-5wt.% ) to the eutectic In-Sn solder. Lap joints were fabricated between YBCO tapes using these solders and were characterized for electrical resistivity, microstructure, and mechanical properties. According to the results, Ag addition changes the solder bulk structure with minimum impact on the interface and mainly dissolves in the In-rich phase of the solder. The joints made with Ag-added solders show significantly higher mechanical strength and ductility, with fracture shifting from the joint to the tape outside the joint region, and reasonably low electrical resistance. The optimized 5wt.% Ag addition to the binary In-Sn solder showed the best compromised joining performance as a result of a homogenous joint microstructure, offering a promising approach towards more reliable joints for superconducting magnet applications.
{"title":"Development of Ag-Added InSn Solders for ReBCO Joints","authors":"Nooshin Goodarzi;Kévin Berger;Alexander Molodyk;Mark Ainslie;Tayebeh Mousavi","doi":"10.1109/TASC.2025.3646983","DOIUrl":"https://doi.org/10.1109/TASC.2025.3646983","url":null,"abstract":"This study explores ternary Ag-added InSn solders to develop low-resistance, reliable, and mechanically robust joints between YBCO tapes, an essential requirement for superconducting magnets, including the magnets in the fusion industry. To investigate the impact of Ag addition to the widely used SnIn solder, several solders were made by adding small amounts of Ag (1-5wt.% ) to the eutectic In-Sn solder. Lap joints were fabricated between YBCO tapes using these solders and were characterized for electrical resistivity, microstructure, and mechanical properties. According to the results, Ag addition changes the solder bulk structure with minimum impact on the interface and mainly dissolves in the In-rich phase of the solder. The joints made with Ag-added solders show significantly higher mechanical strength and ductility, with fracture shifting from the joint to the tape outside the joint region, and reasonably low electrical resistance. The optimized 5wt.% Ag addition to the binary In-Sn solder showed the best compromised joining performance as a result of a homogenous joint microstructure, offering a promising approach towards more reliable joints for superconducting magnet applications.","PeriodicalId":13104,"journal":{"name":"IEEE Transactions on Applied Superconductivity","volume":"36 5","pages":"1-5"},"PeriodicalIF":1.8,"publicationDate":"2026-01-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145982295","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}
We present the design and testing of a prototype multiplexing kinetic inductance detector readout electronics for the PRobe far-Infrared Mission for Astrophysics (PRIMA) space mission. PRIMA is a Probe-class astrophysics mission concept that will answer fundamental questions about the formation of planetary systems, the coevolution of stars and supermassive black holes in galaxies, and the rise of heavy elements and dust over cosmic time. The readout electronics for PRIMA must be compatible with operation at Earth–Sun L2 and capable of multiplexing more than 1000 detectors over 2.5-GHz bandwidth. The electronics must also be capable of switching between the two instruments, which have different readout bands: the hyperspectral imager (PRIMAger, 2.6–4.9 GHz) and the spectrometer (Far-Infrared Enhanced Survey Spectrometer, 0.4–2.4 GHz). The PRIMA readout electronics use high-heritage SpaceCube digital electronics with a build-to-print SpaceCube Mini v3.0 board using a radiation-tolerant Kintex KU060 field programmable gate array and a custom high-speed digitizer board, along with radio frequency electronics that provide filtering and power conditioning. We present the driving requirements for the system, as well as the hardware, firmware, software, and system-level design that meets those requirements.
本文介绍了用于远红外天体物理探测任务（PRIMA）空间任务的多路复用动态电感探测器读出电子元件的原型设计和测试。PRIMA是一个探测器级的天体物理学任务概念，它将回答有关行星系统的形成、星系中恒星和超大质量黑洞的共同演化以及宇宙时间中重元素和尘埃的上升等基本问题。PRIMA的读出电子设备必须与地球-太阳L2的操作兼容，并且能够在2.5 ghz带宽上复用超过1000个探测器。电子设备还必须能够在两种仪器之间切换，这两种仪器具有不同的读数波段：高光谱成像仪（PRIMAger, 2.6-4.9 GHz）和光谱仪（远红外增强巡天光谱仪，0.4-2.4 GHz）。PRIMA读出电子设备使用高传承的SpaceCube数字电子设备，内置打印SpaceCube Mini v3.0板，使用耐辐射的Kintex KU060现场可编程门阵列和定制的高速数字化仪板，以及提供滤波和电源调节的射频电子设备。我们提出了该系统的驱动需求，以及满足这些需求的硬件、固件、软件和系统级设计。
{"title":"Spaceflight KID Readout Electronics for PRIMA","authors":"Thomas Essinger-Hileman;C. Matt Bradford;Patrick Brown;Sean Bryan;Jesse Coldsmith;Jennifer Corekin;Sumit Dahal;Thomas Devlin;Marc Foote;Draisy Friedman;Alessandro Geist;Jason Glenn;Christopher Green;Tracee Jamison-Hooks;Kevin Horgan;Jared Lucey;Philip Mauskopf;Lynn Miles;Sanetra Bailey Newman;Gerard Quilligan;Cody Roberson;Adrian Sinclair;Salman Sheikh;Eric Weeks;Christopher Wilson;Travis Wise","doi":"10.1109/TASC.2026.3652455","DOIUrl":"https://doi.org/10.1109/TASC.2026.3652455","url":null,"abstract":"We present the design and testing of a prototype multiplexing kinetic inductance detector readout electronics for the PRobe far-Infrared Mission for Astrophysics (PRIMA) space mission. PRIMA is a Probe-class astrophysics mission concept that will answer fundamental questions about the formation of planetary systems, the coevolution of stars and supermassive black holes in galaxies, and the rise of heavy elements and dust over cosmic time. The readout electronics for PRIMA must be compatible with operation at Earth–Sun L2 and capable of multiplexing more than 1000 detectors over 2.5-GHz bandwidth. The electronics must also be capable of switching between the two instruments, which have different readout bands: the hyperspectral imager (PRIMAger, 2.6–4.9 GHz) and the spectrometer (Far-Infrared Enhanced Survey Spectrometer, 0.4–2.4 GHz). The PRIMA readout electronics use high-heritage SpaceCube digital electronics with a build-to-print SpaceCube Mini v3.0 board using a radiation-tolerant Kintex KU060 field programmable gate array and a custom high-speed digitizer board, along with radio frequency electronics that provide filtering and power conditioning. We present the driving requirements for the system, as well as the hardware, firmware, software, and system-level design that meets those requirements.","PeriodicalId":13104,"journal":{"name":"IEEE Transactions on Applied Superconductivity","volume":"36 6","pages":"1-5"},"PeriodicalIF":1.8,"publicationDate":"2026-01-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146175891","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}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：