Article
Engineering, Electrical & Electronic
Wolfgang Weingarten
Summary: Small weak superconducting defects located at the surface, along with proximity and percolation effects, are found to be responsible for various observations in superconducting RF cavities. These include nonconstant Q-values, Q-slope and Q-drop, temperature effects, nitrogen doping, and the influence of external magnetic fields. The findings are confirmed using the Ginzburg-Landau equations.
IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY
(2023)
Article
Physics, Applied
S. Leith, M. Vogel, J. Fan, E. Seiler, R. Ries, X. Jiang
Summary: In recent years, researchers have shown increased interest in alternatives to bulk Nb for superconducting radio frequency (SRF) cavities, particularly focusing on thin films of Nb or other high T-c materials. Recent insights into the potential of single layer high -kappa materials have sparked additional research in this area.
SUPERCONDUCTOR SCIENCE & TECHNOLOGY
(2021)
Article
Multidisciplinary Sciences
Sachin Yadav, Vinay Kaushik, M. P. Saravanan, R. P. Aloysius, V Ganesan, Sangeeta Sahoo
Summary: Disorder induced phase slip events were observed in current voltage characteristics of two-dimensional TiN thin films produced through robust substrate mediated nitridation technique. The critical temperature and resistive steps in the characteristics were found to vary strongly with annealing temperature and thickness, indicating the robustness of the synthesis process in fabricating disordered nitride-based superconductor.
SCIENTIFIC REPORTS
(2021)
Article
Physics, Applied
R. Ries, E. Seiler, F. Gomory, A. Medvids, P. Onufrijevs, C. Pira, E. Chyhyrynets, O. B. Malyshev, R. Valizadeh
Summary: Superconducting radiofrequency (SRF) cavities are vital components of particle accelerators. This study investigates the surface quality of Nb film samples on Cu substrates, categorizing surface defects as hills, pits, and cracks. Through numerical finite-element simulations, the factor beta, which characterizes local magnetic field enhancement, is calculated. The study finds a linear relationship between the local magnetic field enhancement and the first entry field (H(en)), indicating that the magnetic field penetration is affected by the defects causing the highest field enhancement.
SUPERCONDUCTOR SCIENCE & TECHNOLOGY
(2022)
Article
Physics, Applied
Kevin M. Ryan, Carlos G. Torres-Castanedo, Dominic P. Goronzy, David A. Garcia Wetten, Mark Field, Cameron J. Kopas, Jayss Marshall, Matthew J. Reagor, Michael J. Bedzyk, Mark C. Hersam, Venkat Chandrasekhar
Summary: Continued advances in superconducting qubit performance require a better understanding of the sources of decoherence. Defects in Nb films are thought to be a major cause of qubit decoherence. By measuring the variation of the superconducting critical temperature with an applied magnetic field, the properties of Nb films and different treatments can be evaluated quickly.
APPLIED PHYSICS LETTERS
(2022)
Article
Physics, Applied
Marc Wenskat, Getnet Kacha Deyu, Isabel Gonzalez Diaz-Palacio, Robert H. Blick, Robert Zierold, Wolfgang Hillert
Summary: Surface modification of SRF cavities is crucial for advancing future accelerators, and one effective method is depositing multilayer superconducting and insulating materials on the inner surface. In this study, we successfully coated an SRF cavity with low-temperature insulating Al2O3 -1 and observed an improvement in surface resistance above 30 MV m(-1), likely due to enhanced oxygen diffusion during the deposition process. Our results demonstrate the suitability of ALD for providing conformal coating and modifying the properties of such devices.
SUPERCONDUCTOR SCIENCE & TECHNOLOGY
(2023)
Article
Chemistry, Physical
T. Roch, M. Gregor, S. Volkov, M. Caplovicova, L. Satrapinskyy, A. Plecenik
Summary: This study examined the impact of different substrates on the structure and orientation of niobium nitride thin films, revealing that films on C-Al2O3 substrate exhibited the best superconducting properties.
APPLIED SURFACE SCIENCE
(2021)
Article
Physics, Applied
A. Prudnikava, Y. Tamashevich, S. Babenkov, A. Makarova, D. Smirnov, V Aristov, O. Molodtsova, O. Kugeler, J. Viefhaus, B. Foster
Summary: This study investigates the effects of nitrogen infusion and thermal treatment on the formation of oxides in niobium RF cavities. The results show that nitrogen has no effect on the formation of oxides, while the cleanliness of the vacuum furnace during the high-temperature stage is crucial for the success of any treatment process.
SUPERCONDUCTOR SCIENCE & TECHNOLOGY
(2022)
Article
Nanoscience & Nanotechnology
Li Yang, Baiqi Liu, Zongbiao Ye, Chi Yang, Zhijun Wang, Bo Chen, Jianjun Chen, Peng Sha, Chao Dong, Jie Zhu, Zhiling Li, Rong Yan, Rui Ding, Kun Zhang, Fujun Gou
Summary: Different methods were used to analyze the surface morphology and depth composition of nitrogen-doped niobium. The results showed densely distributed trigonal precipitates on the surface after nitrogen doping, and beta-Nb2N was dominant in the topmost 9.7 nm extending to a depth of 575 nm.
Article
Materials Science, Multidisciplinary
Yuan Zhong, Zegang Ni, Jinjin Li, Xu Li, Wenhui Cao, Xueshen Wang, Qing Zhong, Xiaolong Xu, Jian Chen, Congcong Liang
Summary: In this study, RF-biased DC magnetron sputtering was used to improve the surface roughness and superconducting properties of Nb thin films. Increased RF power reduced surface roughness but also had negative effects on other performance indicators. The microstructures, impurities, and dislocation states were found to be correlated with the electrical and superconducting properties of the films.
Article
Chemistry, Physical
Bryan Horcholle, Christophe Labbe, Xavier Portier, Philippe Marie, Cedric Frilay, Weiqiang Yuan, Wojciech Jadwisienczak, David Ingram, Clara Grygiel, Julien Cardin
Summary: Undoped and doped Nb2O5 thin films were successfully deposited on silicon wafer using sputtering technique and annealed to investigate their chemical, structural, optical, and photoluminescent properties. The study revealed the stoichiometry, phase transformations, refractive index, and electronic properties evolution of the films with annealing temperature and Tb3+ ion content. Raman spectra analysis confirmed the structural evolution, while the correlation between photoluminescence and electronic properties was highlighted.
APPLIED SURFACE SCIENCE
(2022)
Article
Physics, Applied
Zeming Sun, Zhaslan Baraissov, Catherine A. Dukes, Darrah K. Dare, Thomas Oseroff, Michael O. Thompson, David A. Muller, Matthias U. Liepe
Summary: The surface compositions, structural profiles, and valence distributions of niobium and niobium-tin under different processing conditions were investigated. It was found that carbide formation during high-temperature baking determines subsequent oxide formation, which has important implications for ultra-high vacuum baking and nitrogen processing. Additionally, vapor-diffused Nb3Sn contains thick metastable oxides, while electrochemically synthesized Nb3Sn only has a thin oxide layer.
SUPERCONDUCTOR SCIENCE & TECHNOLOGY
(2023)
Article
Physics, Applied
Wanshuo Sun, Junsheng Cheng, Shunzhong Chen
Summary: Nb3Sn was successfully prepared by mechanical alloying and heat treatment. With the increase of milling time and the addition of copper powder, the powders become more homogeneous. The introduction of a small amount of stearic acid relieved the phenomenon of powder adhering to the wall and greatly reduced the time needed for heat treatment.
JOURNAL OF LOW TEMPERATURE PHYSICS
(2021)
Review
Quantum Science & Technology
Xiaoping Yang, Miao Li, Zhenyu Ding, Liangyu Li, Ce Ji, Gang Wu
Summary: The rapid development of modern heterointerface growth and characterization techniques in the past decade has greatly stimulated research and design efforts on the physical properties of transition metal heterostructure composite materials. In this paper, recent experimental and theoretical progresses on the design, preparation, characterization, and physical property measurement of LaNiO3-based heterostructure composites and Ni1 + nickelate superconducting thin films on SrTiO3 substrate are reviewed. The electronic structure and orbital occupation around the Fermi level are modified in these materials, enabling them to exhibit new states of matter and physical phenomena.
ADVANCED QUANTUM TECHNOLOGIES
(2023)
Article
Materials Science, Multidisciplinary
Hiroyuki Hama, Sadao Miura
Summary: Tohoku University constructed a 300 MeV electron linac in 1967 for nuclear physics and neutron science research. Despite some parts collapsing in the 2011 earthquake, high-intensity beams are still supplied. The possibility of introducing a new SRF cavity system to expand research activities is being considered.
PHYSICA STATUS SOLIDI A-APPLICATIONS AND MATERIALS SCIENCE
(2021)
Article
Physics, Applied
Y. Trenikhina, S. Posen, A. Romanenko, M. Sardela, J-M Zuo, D. L. Hall, M. Liepe
SUPERCONDUCTOR SCIENCE & TECHNOLOGY
(2018)
Article
Physics, Applied
M. Checchin, M. Martinello, A. Grassellino, S. Aderhold, S. K. Chandrasekaran, O. S. Melnychuk, S. Posen, A. Romanenko, D. A. Sergatskov
APPLIED PHYSICS LETTERS
(2018)
Article
Instruments & Instrumentation
D. Gonnella, S. Aderhold, A. Burrill, E. Daly, K. Davis, A. Grassellino, C. Grimm, T. Khabiboulline, F. Marhauser, O. Melnychuk, A. Palczewski, S. Posen, M. Ross, D. Sergatskov, A. Sukhanov, Y. Trenikhina, K. M. Wilson
NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT
(2018)
Article
Physics, Multidisciplinary
M. Martinello, M. Checchin, A. Romanenko, A. Grassellino, S. Aderhold, S. K. Chandrasekeran, O. Melnychuk, S. Posen, D. A. Sergatskov
PHYSICAL REVIEW LETTERS
(2018)
Article
Physics, Applied
Jaeyel Lee, Sam Posen, Zugang Mao, Yulia Trenikhina, Kai He, Daniel L. Hall, Matthias Liepe, David N. Seidman
SUPERCONDUCTOR SCIENCE & TECHNOLOGY
(2019)
Article
Physics, Nuclear
S. Posen, G. Wu, A. Grassellino, E. Harms, O. S. Melnychuk, D. A. Sergatskov, N. Solyak, A. Romanenko, A. Palczewski, D. Gonnella, T. Peterson
PHYSICAL REVIEW ACCELERATORS AND BEAMS
(2019)
Article
Engineering, Electrical & Electronic
Rain C. Dhulcy, Roman Kostin, Oleg Prokofiev, Michael Geelhoed, Thomas H. Nicol, Sam Posen, Jayakar Charles Tobin Thangaraj, Thomas K. Kroc, Robert D. Kephart
IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY
(2019)
Article
Physics, Applied
S. Posen, A. Romanenko, A. Grassellino, O. S. Melnychuk, D. A. Sergatskov
PHYSICAL REVIEW APPLIED
(2020)
Article
Materials Science, Multidisciplinary
Jaeyel Lee, Zugang Mao, Kai He, Zu Hawn Sung, Tiziana Spina, Sung-Il Baik, Daniel L. Hall, Matthias Liepe, David N. Seidman, Sam Posen
Article
Physics, Applied
R. C. Dhuley, S. Posen, M. Geelhoed, O. Prokofiev, J. C. T. Thangaraj
SUPERCONDUCTOR SCIENCE & TECHNOLOGY
(2020)
Article
Physics, Applied
S. Posen, J. Lee, D. N. Seidman, A. Romanenko, B. Tennis, O. S. Melnychuk, D. A. Sergatskov
Summary: Nb3Sn is a promising material for superconducting radiofrequency cavities, showing potential for higher accelerating fields and industrial accelerator applications. New results include higher field strengths in single cell cavities and the first Nb3Sn-coated 9-cell cavity demonstration. The study reveals smooth surfaces, reduced film thickness, and implications for RF superconductivity physics.
SUPERCONDUCTOR SCIENCE & TECHNOLOGY
(2021)
Article
Physics, Nuclear
S. Posen, A. Cravatta, M. Checchin, S. Aderhold, C. Adolphsen, T. Arkan, D. Bafia, A. Benwell, D. Bice, B. Chase, C. Contreras-Martinez, L. Doolittle, J. Fuerst, D. Gonnella, A. Grassellino, C. Grimm, B. Hansen, E. Harms, B. Hartsell, G. Hays, J. Holzbauer, S. Hoobler, J. Kaluzny, T. Khabiboulline, M. Kucera, D. Lambert, R. Legg, F. Lewis, J. Makara, H. Maniar, J. T. Maniscalco, M. Martinello, J. Nelson, S. Paiagua, Y. Pischalnikov, P. Prieto, J. Reid, M. Ross, C. Serrano, N. Solyak, A. Syed, D. Sun, G. Tatkowski, R. Wang, M. White, L. Zacarias
Summary: A novel high energy cryomodule was tested at Fermilab, demonstrating excellent performance exceeding specifications by improving gradient performance and addressing sporadic quenches issues.
PHYSICAL REVIEW ACCELERATORS AND BEAMS
(2022)
Article
Physics, Nuclear
B. Giaccone, P. Berrutti, M. Martinello, S. Posen, A. Cravatta, A. Netepenko, T. Arkan, A. Grassellino, B. Hartsell, J. Kaluzny, A. Penhollow, D. Gonnella, M. Ross, J. Fuerst, G. Hays, J. T. Maniscalco, M. Doleans
Summary: This article presents the application of plasma cleaning technique in superconducting radio-frequency cavities to reduce field emission and multipacting issues. The results show that plasma processing preserves cavity performance and eliminates contaminants, offering potential benefits for cryomodule testing and linac commissioning.
PHYSICAL REVIEW ACCELERATORS AND BEAMS
(2022)
Article
Engineering, Electrical & Electronic
R. Kostin, C. Jing, S. Posen, T. Khabiboulline, D. Bice
Summary: RF (SRF) photoguns are emerging as promising candidates for Ultra fast Electron Diffraction/Microscopy (EUD/UEM) applications due to their ultrahigh shot-to-shot stability compared to room temperature RF photoguns. Recent advancements in Nb3Sn and conduction cooling have made SRF technology more affordable for industrial use. Euclid is developing a 1.3 GHz, continuous wave (CW), 1.5-cell, MeV-scale SRF conduction cooled photogun and this paper presents the first high power results of the gun covered with Nb3Sn.
IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY
(2023)
Article
Engineering, Electrical & Electronic
E. Viklund, J. Lee, D. N. Seidman, S. Posen
Summary: Niobium has been the preferred material for SRF cavities, but its accelerating gradient is reaching its limit. Nb3Sn is a potential alternative with higher superconducting properties, but its brittleness hinders cavity formation. This study analyzes the 3-D structure of Nb3Sn films using focused ion beam tomography and reveals tin-deficient regions near the surface.
IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY
(2023)
