Advances In Superconductivity

Intense recent activity in the field of high-temperature superconductivity both in Japan and in the rest of the world was discussed at the First International Symposium on Superconductivity held in Nagoya in August 1988. Current research and development efforts by major Japanese companies in the field of high-temperature superconductivity are reported by leading company scientists, to give an overview of the high level of activity in the area. Progress in the development of new materials and recent theoretical work is reported both from Japanese and international researchers. Contributions are organized by topic, with such topics as crystal chemistry and electronic structure, processing and microstructure, tapes and thick films, wires and coils, and thin film processing and properties. Future applications of superconductivity including magnetic levitation vehicles, electronics based on Josephson junctions, power delivery, energy storage, ship propulsion and magnetic resonance imaging are particularly stressed.

More than seven years have passed since the dramatic breakthrough in the critical temperature for superconductors. During this period, a host of new materials have been discovered, and efforts have been stepped up in a variety of domains including device and systems applications, commercialization, and basic research on the properties of superconductive materials. Recent progress in areas such as bulk single crystal production, long-scale wire and tape produc tion, flywheel and bearing applications, and electronic device applications for thin films indicate that science and technology have been working hand in hand in this field, as has been the case in the research and development of semi conductors. This interdisciplinary "resonance" will be certain to lead to further outstanding advances in the years to come. It goes without saying that worldwide information exchange is the key to accelerating progress in superconductivity science and technology. As in previous years, the ISS '93 served as a venue where visions of future develop ments were shared in addition to presentations and extensive discussions on the most up-to-date research results. I hope that the Proceedings contained in this volume will be consulted not only as a summary of the current "state of the art" in high-Tc superconductivity but also as a stimulating source of ideas regarding future applications of superconductivity research.

Theory of Superconductivity is considered one of the best treatment of the field. This monograph, by Nobel Prize-winning physicist J. Robert Schrieffer, has been reprinted because of its enduring value as an introduction to the theory of superconductivity. The fundamentals of the theory of superconductivity are stresses as a means of providing the reader with a framework for the literature in which detailed applications of the microscopic theory are made to specific problems. It also serves as a foundation for the more recent development in this active field.

The International Symposium on Superconductivity, which has been held annu ally since 1988, is a forum for presenting the most up-to-date information about a broad range of research and development in superconductivity, from funda mental aspects to applications. More than 10 years have passed since the discovery of oxide superconductors and since various developments of applications began. It may be said that the prospects for application of oxide superconductors recently have opened up. Great progress has been made toward practical use, for example, of the flywheel, which uses bulk materials, and the high-performance cryo-cooled magnet made of bismuth wire. These were the results of persistent efforts to develop materials from the viewpoint of materials science and engineering. Also important is the progress in comprehensive understanding of high temperature superconductivity. Unique electronic properties of cuprates such as the non-Fermi liquid normal state, spin-charge separation, spin gap, and d-wave symmetry were discussed at the symposium, as were the unique electromagnetic properties resulting from the low dimensionality of cuprates. In the field of new superconductors, many exotic materials have been discovered since 1986. A decade of work with cuprate superconductors is reviewed in this proceedings, and several of the newest materials are presented. These papers will be instructive for many researchers and for students who are to enter this field.

This book is a printed edition of the Special Issue "Advances in Organic Conductors and Superconductors" that was published in Crystals

The field of high-temperature superconductivity has encouraged an inter disciplinary approach to research. It has required significant cooperation and collaboration among researchers, each of whom has brought to it a rich variety of experience from many other fields. Recently, great improvements have been made in the quality of research. The subject has matured and been launched into the next stage through the resonance between science and technology. The current progress of materials processing and engineering in this field is analogous to that previously seen in the development of semiconductors. These include the appearance of materials taking the place of YBa2Cu307 owing to their improved properties (higher critical temperatures and stronger flux pin ning) in which rare earth ions with large radii (La, Nd, Sm) substitute for Y; the development of technology enabling growth control on the nanometer scale; and precise and reproducible measurements that can be used as rigorous tests of theoretical models, which in turn are expected to lead to the develop ment of new devices. For further progress in high-T research, academics and c technologists must pool their knowledge and experience. I hope that this volume will promote that goal by providing the reader with the latest results of high-temperature superconductor research and will stimulate further discussion and collaboration.

The 12th International Symposium on Superconductivity was held in Morioka, Japan, October 17-19, 1999. Convened annually since 1988, the symposium covers the whole field of superconductivity from fundamental physics and chemistry to a variety of applications. At the 12th Symposium, a mini-symposium focusing on the two-dimensionality of high-temperature superconductors, or the c-axis transport, and a session on vortex physics were organized. There were also many reports on the recent developments of YBCO-based coated conductors both in the United States and in Japan, AC losses of wires and tapes, developments of bulk materials with strong flux pinning, the recent progress in thin film and junction technologies, and the demonstration of various electronics applications using SQUIDs, microwave devices, and single-flux-quantum (SFQ) digital devices. This volume is a valuable resource for all those working in the field of superconductivity.

This book covers all research fields in high Tc Superconductivity. Breakthrougs in the single crystal growth of a monolithic device leads to a new technology.

The 11th International Symposium on Superconductivity was held November 16-19, 1998, in Fukuoka, Japan. Convened annually since 1988, the symposium covers the whole field of superconductivity from fundamental physics and chemistry to new applications. At the 11th Symposium, there was increased interest reported in the development of trial devices using bismuth wires and yttrium-based bulk materials. Among the presentations were those that clearly defined the development targets for next-generation yttrium-based wires and bulk materials and single-flux quantum (SFQ) circuits. Other popular topics were high-temperature superconductivity applications such as SQUIDs, microwave filters, and cryocooler-cooled magnets. With more than 600 participants from 18 countries, the symposium provided an excellent forum for exchanges of the most recent information in the field of superconductivity.