Journal: Superconductor Science and Technology

Abbreviation

Supercond. Sci. Technol.

Publisher

IOP Publishing

Journal Volumes

ISSN

0953-2048
1361-6668

Description

Filters

Reset filters

Search Results

Publications 1 - 10 of 16
  • Crystal-edge scanning tunnelling spectroscopy on aluminium-doped magnesium diboride
    Item type: Journal Article
    Dubois, C.; Jenkins, N.; Manuel, A.A.; et al. (2006)
    Superconductor Science and Technology
  • Ac losses in field-cooled type I superconducting cavities
    Item type: Journal Article
    Catelani, Gianluigi; Li, K.; Axline, Christopher James; et al. (2022)
    Superconductor Science and Technology
    As superconductors are cooled below their critical temperature, stray magnetic flux can become trapped in regions that remain normal. The presence of trapped flux facilitates dissipation of ac current in a superconductor, leading to losses in superconducting elements of microwave devices. In type II superconductors, dissipation is well-understood in terms of the dynamics of vortices hosting a single flux quantum. In contrast, the ac response of type I superconductors with trapped flux has not received much attention. Building on Andreev's early work (Andreev 1967 Sov. Phys. JETP 24 1019), here we show theoretically that the dominant dissipation mechanism is the absorption of the ac field at the exposed surfaces of the normal regions, while the deformation of the superconducting/normal interfaces is unimportant. We use the developed theory to estimate the degradation of the quality factors in field-cooled cavities, and we satisfactorily compare these theoretical estimates to the measured field dependence of the quality factors of two aluminum cavities. We also identify a regime in which the dissipated power depends weakly on the Ginzburg-Landau parameter; this makes it possible to apply our findings to cavities made of other materials, such as niobium.
  • Order-disorder transition in the flux line lattice of superconducting MgB2 single crystals with artificially introduced defects
    Item type: Journal Article
    Zehetmayer, M.; Eisterer, M.; Krutzler, C.; et al. (2007)
    Superconductor Science and Technology
  • Comparison of the influence of carbon substitution and neutron-induced defects on the upper critical field and flux pinning in MgB2 single crystals
    Item type: Journal Article
    Wisniewski, A.; Puzniak, R.; Judek, J.; et al. (2007)
    Superconductor Science and Technology
  • Point-Contact Spectroscopy in MgB2: from Fundamental Physics to Thin-Film Characterization
    Item type: Conference Paper
    Gonelli, Renato S.; Daghero, Dario; Calzolari, Arrigo; et al. (2004)
    Superconductor Science and Technology
    In this paper we highlight the advantages of using point-contact spectroscopy (PCS) in multigap superconductors like MgB2, both as a fundamental research tool and as a non-destructive diagnostic technique for the optimization of thin-film characteristics. We first present some results of crucial fundamental interest obtained by directional PCS in MgB2 single crystals, for example the temperature dependence of the gaps and of the critical fields, and the effect of a magnetic field on the gap amplitudes. Then, we show how PCS can provide useful information about the surface properties of MgB2 thin films (e.g., Tc, gap amplitude(s), clean- or dirty-limit conditions) in view of their optimization for the fabrication of tunnel and Josephson junctions for applications in superconducting electronics.
  • Prediction of resistive and hysteretic losses in a multi-layer high-T-c superconducting cable F Grilli M Sjöström
    Item type: Journal Article
    Grilli, F.; Sjöström, M. (2004)
    Superconductor Science and Technology
  • 23 Tesla high temperature superconducting pocket magnet
    Item type: Journal Article
    Gao, Chukun; Chen, Pin-Hui; Alaniva, Nicholas; et al. (2024)
    Superconductor Science and Technology
    We present a compact 23 T no-insulation (NI) magnet that was wound with 60 m of 10 mm wide high temperature superconducting (HTS) tape. The magnet consists of only one pocket-sized double pancake (DP) coil with an inner diameter of ∼6 mm, a height of 20 mm, and an outer diameter of 41.6 mm. Another NI coil of similar size but with a larger inner diameter of 8 mm reached a slightly lower magnetic field of 21 T. We also present a smaller coil which was wound with only 20 m of HTS tape and still achieved a magnetic field of 16 T. During the experiments in liquid helium, each coil was charged to a current between 690 A and 850 A, corresponding to a high current density of 1500–1900 A mm−2. The small bore size and high current density contributed to the high fields generated by these coils. We present the fabrication details, helium tests and repeatability analysis of these 'pocket' magnets.
  • Record field in a 10 mm-period bulk high-temperature superconducting undulator
    Item type: Journal Article
    Zhang, Kai; Pirotta, Andrew; Liang, Xiaoyang; et al. (2023)
    Superconductor Science and Technology
    A 10 mm-period, high-temperature superconducting (HTS) undulator consisting of 20 staggered-array GdBa2Cu3O7−x (GdBCO) bulk superconductors has been fabricated and tested successfully. Each GdBCO disk was machined into a half-moon shape with micro-meter accuracy and shrink-fitted into a slotted oxygen-free copper disk which provided pre-stress and effective conduction-cooling. The HTS undulator prototype, consisting of GdBCO disks, copper disks, and CoFe poles fitted in a long copper shell, was field-cooled magnetized in fields of up to 10 T at 10 K. An undulator field of 2.1 T in a 4 mm magnetic gap was obtained. This field is the largest reported yet for the same gap and period length and exceeds the target value of 2 T for the meter-long HTS undulator scheduled for the hard x-ray I-TOMCAT beamline in the Swiss Light Source 2.0. We have demonstrated that bulk superconductor based undulators can provide significantly improved performance over alternative technologies.
  • Effects of proton irradiation and ageing on the superconducting properties of single crystalline and polycrystalline MgB2
    Item type: Journal Article
    Perkins, G.K.; Bugoslavsky, Y.; Caplin, A.D.; et al. (2004)
    Superconductor Science and Technology
  • Disorder effects and current percolation in FeAs-based superconductors
    Item type: Journal Article
    Eisterer, M.; Zehetmayer, M.; Weber, H.W.; et al. (2010)
    Superconductor Science and Technology
Publications 1 - 10 of 16