Physics and Materials Science of High Temperature Superconductors, IV

Five questions dominated the ARW on Physics and Materials Science of High Temperature Superconductors , of which this book forms the permanent record. Briefly, these are: (i) How close are we to a unified theory? The consensus is that we are not. (ii) Flux pinning: can it be achieved in bulk materials? Still an open question. The following three questions are related. (iii) Can grain boundary contributions be brought under control? (iv) What is the real requirement for purity and general chemistry control? (v)What is the practical outlook for bulk products - tapes and wires? One of the conclusions is that the geometry and dimensions in thin films are the key parameters that facilitate the realization of high current densities and, consequently, their commercial application. On the other hand, the very large number of poorly understood microstructural, chemical and mechanical variables involved in the preparation of bulk materials are currently prohibiting large scale commercialization of wires and tapes.

Klappentext

Five questions dominated the ARW on Physics and Materials Science of High Temperature Superconductors, of which this book forms the permanent record. Briefly, these are: (i) How close are we to a unified theory? The consensus is that we are not. (ii) Flux pinning: can it be achieved in bulk materials? Still an open question. The following three questions are related. (iii) Can grain boundary contributions be brought under control? (iv) What is the real requirement for purity and general chemistry control? (v)What is the practical outlook for bulk products - tapes and wires? One of the conclusions is that the geometry and dimensions in thin films are the key parameters that facilitate the realization of high current densities and, consequently, their commercial application. On the other hand, the very large number of poorly understood microstructural, chemical and mechanical variables involved in the preparation of bulk materials are currently prohibiting large scale commercialization of wires and tapes.

Zusammenfassung
Proceedings of the NATO Advanced Research Workshop, Strbske Pleso, Slovak Republic, July 21-27, 1996

Inhalt
I: Physics and Theory.- Abrikosov Vortices Behavior in Different Pinning Potential for Moderately Anisotropic High-Tc Superconductors.- Microwave Dissipation and the Structure of the Vortex Lattice in Bi2Sr2CaCu208+? Single Crystals.- The Flux Line Lattice States in Single-Crystalline Superconductors with Weak Pinning.- Can We Achieve High In-Field Jc at 77 K in Bi-Sr-Ca-Cu-O?.- The Violation of the BCS Theory and the Extensions Required to Include the Effects of a Nearby Phase Transition.- Correlations Between Magnetostriction Jumps and Flux Instabilities in La1.85Sr0.15CuO4 Single Crystal.- Spin-Phonon Correlations and Optical Excitations in Oxides.- Anisotropic Josephson Junctions on Stepped Surfaces of Bi2Sr2CaCu2O8 Crystals: Evidence for the Symmetry of the Pair Wave Function.- II: Processing and Properties - Crystals.- Material Science Aspects of HTS Technical Superconductors.- Studies of Infinite-Layer T' -Phase and 1-D-Ladder Copper-Oxide Compounds.- Low-Temperature H-T Phase Diagram of Nd1.85Ce0.15CuO4±?.- Superconductivity in the La2CuO4.03 Single Crystal System.- Residual Microstresses a-b Microcracking and Twin Structure in Oxygen Controlled Melt Grown NdBaCuO Superconductors.- Microstructure and Superconducting Characteristics of HgmPbnBa2Ca2Cu3O8+?.- Problems of Searching for Copper-Free HTSC Compositions.- III: Processing and Properties - Thin Films.- Pulsed Laser Deposition of Thin Films.- Study of a-Axis Oriented YBa2Cu3Ox Superconducting Thin Films on Y2O3/YSZ/Si Substrates.- Structural Disorder Investigations of YBCO Thin Films Using Raman Microscopy.- Penetration Depth Measurements in Epitaxiel YBCO Thin Films by the ESR Technique.- IV: Applications.- HTS Multilayer Process Development for Digital Circuits.- Evaluation of the MagneticProperties of Nd-Based Superconductors.- Noise Properties of HTSC Films for Bolometers on Si Membranes.- Application of Ion Beam Etching to Investigate the Electrical Behaviour of Josephson Junctions.- Synthesis of Bi-Sr-Ca-Cu-O Wires for Perspective Applications.- Late Submission.- Electron-Density Distribution and valence-Bond Structure in Copper-Oxygen Linkage in YBA2Cu3O6.9 and CuGeO3.- List of Participants.