Journal ArticleDOI
Structural origin of reduced critical currents at YBa2Cu3O7–δ grain boundaries
TLDR
In this article, a simple model of the strain associated with the grain-boundary dislocations provides a reasonable physical explanation of the suppressed superconductivity of YBa2Cu3O7−δ.Abstract:
THE critical current density across individual grain boundaries in thin films of the high-Tc superconductor YBa2Cu3O7–δ (YBCO) has been found1–4 to be inversely proportional to lattice misorientation for tilts up to ∼10°. Reports of impurity segregation5,6 at grain boundaries, and variations in the chemical stoichiometry7,8, have led to the view that deviations from the ideal composition are responsible for the depressed superconducting order parameter at the boundary. Here we present images of YBCO grain boundaries obtained by a scanning transmission electron microscope in Z-contrast mode9,10, which show that chemical segregation does not necessarily occur at these boundaries. A simple model of the strain associated with the grain-boundary dislocations provides a reasonable physical explanation of the suppressed superconductivity. The surprisingly large effect of strain implied by our model has implications beyond critical currents, for the physics and applications of any thin-film YBCO structures involving strained epitaxial layers.read more
Citations
More filters
Journal ArticleDOI
Grain boundaries in high- T c superconductors
Hans Hilgenkamp,Jochen Mannhart +1 more
TL;DR: In this article, the authors provide a review of grain boundary properties and their applications in high-Tc superconductivity and high-power and electronic device applications, as well as the theoretical models developed to describe grain boundary behavior.
Journal ArticleDOI
Epitaxial YBa2Cu3O7 on Biaxially Textured Nickel (001): An Approach to Superconducting Tapes with High Critical Current Density
David P. Norton,Amit Goyal,John D. Budai,David K. Christen,Donald M. Kroeger,Eliot D. Specht,Q. He,Bernd Saffian,Mariappan Parans Paranthaman,C.E. Klabunde,Dominic F. Lee,Brian C. Sales,Fred List +12 more
TL;DR: In this article, an inplane aligned, c axis-oriented YBa2Cu3O7 (YBCO) films with superconducting critical current densities Jc as high as 700,000 amperes per square centimeter at 77 kelvin have been grown on thermomechanically rolled-textured nickel (001) tapes by pulsed-laser deposition.
Journal ArticleDOI
Magneto-optical studies of current distributions in high-Tc superconductors
TL;DR: In this paper, a review of the magneto-optical imaging technique and experiments on thin films, single crystals, polycrystalline bulk ceramics, tapes and melt-textured HTS materials is presented.
Journal ArticleDOI
Three-dimensional imaging of dislocations in a nanoparticle at atomic resolution
Chien-Chun Chen,Chun Zhu,Edward R. White,Chin-Yi Chiu,Mary Scott,B. C. Regan,Laurence D. Marks,Yu Huang,Jianwei Miao +8 more
TL;DR: 3D imaging of dislocations in materials at atomic resolution by electron tomography is reported, and nearly all the atoms in a multiply twinned platinum nanoparticle are observed by applying 3D Fourier filtering together with equal-slope tomographic reconstruction.
Journal ArticleDOI
Nanoscale strain-induced pair suppression as a vortex-pinning mechanism in high-temperature superconductors
Anna Llordes,Anna Palau,Jaume Gazquez,Jaume Gazquez,Mariona Coll,R. Vlad,Alberto Pomar,Jordi Arbiol,Jordi Arbiol,Roger Guzmán,Shuai Ye,V. Rouco,Felip Sandiumenge,Susagna Ricart,Teresa Puig,Maria Varela,Daniel Chateigner,Johan Vanacken,J. Gutierrez,Victor Moshchalkov,Guy Deutscher,César Magén,Xavier Obradors +22 more
TL;DR: A new vortex- pinning mechanism based on the bond-contraction pairing model is suggested, where pair formation is quenched under tensile strain, forming new and effective core-pinning regions.
References
More filters
Journal ArticleDOI
Orientation dependence of grain-boundary critical currents in YBa2Cu3O7- delta bicrystals
TL;DR: The results imply that achieving a high degree of texture both normal to and within the basal plane is important for obtaining very high critical currents in pure polycrystalline samples.
Journal ArticleDOI
Superconducting transport properties of grain boundaries in YBa2Cu3O7 bicrystals.
TL;DR: The grain-boundary critical current densities in bicrystal films prepared by evaporation and postannealing and by laser ablation are in good agreement; this result demonstrates that the transport properties are insensitive to preparation technique and, thus, are not dominated by the diffusion of substrate impurities into the boundary region.
Journal ArticleDOI
Chemically sensitive structure-imaging with a scanning transmission electron microscope
TL;DR: In this paper, a high-angle detector in a scanning transmission electron microscope was used to obtain high atomic-number contrast for single crystals of the high-transition-temperature superconductors YBa2Cu3O7-x and ErBa2cu3O 7-x.
Journal ArticleDOI
High-resolution incoherent imaging of crystals
TL;DR: A Bloch-wave analysis shows how a signal dependent on the electron intensity at the atom sites can be used to form an incoherent image of a crystal structure that can be predicted and interpreted intuitively.
Related Papers (5)
Superconducting transport properties of grain boundaries in YBa2Cu3O7 bicrystals.
Current transport through low-angle grain boundaries in high-temperature superconductors
Alex Gurevich,E. A. Pashitskii +1 more