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.

Since the discovery of superconductivity with trans1tton temperatures above 77 K, concentrated research activities toward the exploration of practical applica tions of these materials have been carried out. Currently, a remarkable improve ment in superconducting properties has been achieved due to the fine optimization of fabrication processes, and this has attracted industrial interest for future applications. In the case of NdBa Cu 0 materials, a new pinning mecha 2 3 7 nism was found which enhances the critical current under applied magnetic fields. In single crystals of these materials, oxygen control results in an increase in the growth rate. The metalorganic chemical vapor deposition (MOCVD) film quality has been improved by using a new liquid raw material. Simultaneously, real demands from the viewpoint of the market start to be a motivation force, es pecially in electronics application where some products are already being sold. At the same time, interesting physical properlies have been obtained from a new superconducting single crystal which has a layered perovskite structure without copper. In addition, various precision measurement techniques have confirmed the d-wave mechanism and the existence of intrinsicJosephson junctions in single crystals. These new phenomena challenge the existing theoretical models but also open the way for new applications. These significant areas of progress in materials science have led high-Tc super conductivity research into the next phase of activity, while fundamental research continues to be very important. I sincerely hope that this volume will give further impetus to this development.

In contrast to research on the fundamental mechanisms of High-Temperature Superconductivity, in recent years we have seen enormous developments in the fabrication and application of High-Tc-superconductors. The two volumes of High Temperature Superconductivity provide a survey of the state of the technology and engineering applications of these materials. They comprise extended original research papers and technical review articles written by physicists, chemists, materials scientists and engineers, all of them noted experts in their fields. The interdisciplinary and strictly application-oriented coverage should benefit graduate students and academic researchers in the mentioned areas as well as industrial experts. Volume 1 "Materials" focuses on major technical advancements in High-Tc materials processing for applications. Volume 2 "Engineering Applications" covers numerous application areas where High-Tc superconductors are making tremendous impact.

C axis Current I ~ . The (11 0) thick homoepitaxial film of 320 nm -------~ ~-=-=--==---==--==--==--- shows a very good surface flatness, which --------·· sJ;1 0] suggests the unique (110) atomic plane helps 2- A [1 1 OJ dimensional epitaxial growth of YBCO films, and shows excellent high Tc. The resultant 1. 0 surface morphology of YBCO is quite different Q ,. -- R(270)=1. 60 m 0 from the (110) heteroepitaxial films of similar 0 0. 0 " thickness [11). In the case of heteroepitaxy ~ . ,,_. 1. 0 irrespective of c-axis [ 12] or a-axis oriented ~ ~. . ,. R(270)=3. 71 m 0 films [5), only thin films show flat surfaces, g 0. 0 . . Tc=92. 3K "' which, however, give usually a degraded Tc due -~ 1. 0 v v I - to lattice mismatching. In conclusion, we have ::1. ,. . . . . R(270)=31. 9 mO succeeded to grow high-quality (11 0) YBCO ~ YBCO film . . Tc=90. 7 K 0. 0 ·;:: YBCO(IIO) 1 0 ·d·--~ YBCO thinfilms on (11 0) YBCO single crystal § substrate ~Xtt=u 1. 0 substra substrates with very flat surfaces and high Tc's. :£ R(270)=40. 1 m 0 0. 0 LLLLL. J. . . . LL~. t-J' L-Tc=9LWO. L-! L-K LLLLL. . . . L. . I. . . . l. . . . L. L. L. J. . . . . L. L. l. . . J 50 100 150 200 250 300 0 ACKNOWLEDGMENTS Temperature (K) One of the authors (T. U. ) would like to thank Fig.

High Tc oxide superconductors such as Bi(Pb)-Sr-Ca-Cu-O (BSCCO) and Y-Ba-Cu-O (YBCO) systems are usually fabricated by sintering given mixtures of raw materials. Generally, sintering processing takes a longer heating time and the products are mechanically low strength and cannot be formed into complex shapes such as a coil, a curved fine tube or a fine rod. Another way to produce the ceramics is a glass-ceramic process in which the glasses prepared by melt-quenching are reheated for crystallization. A given mixture of raw materials in BSCCO is easily melted and quenched to form a given shape of glass, while that in YBCO is not glassified.This invaluable book has been written by authors from five countries. It presents a unique way to fabricate superconducting ceramics in BSCCO by glass-ceramic processing.

This volume contains the proceedings of The Second Polish-US Conf- ence on High Temperature Superconductivity which was held August 18-21, 1998 in Karpacz, Poland. The conference followed The First Polish-US C- ference on High Temperature Superconductivity organized in 1995, proce- ings of which were published by Springer-Verlag in 1996 (Recent Devel- ments in High Temperature Superconductivity, Lecture Notes in Physics 475). High Temperature Superconductivity (HTSC) in complex copper oxides has become a household name after twelve years of intense research following its discovery in 1986 by J. G. Bednorz and K. A. Miiller. Because of the rapid growth of the HTSC field, there is a need for periodic summary and conden- tion both for scientists working in the field and, especially, for young resear- ers entering the field of oxide materials. Following the First Conference, it was recognized that an extended format of lectures perfectly satisfied that need, providing adequate time for experts from the international community to fully introduce and develop complex ideas. Thus, the format of the Second Conference brought together by cooperating scientists from the Institute of Low Temperature and Structure Research of the Polish Academy of Science at Wroctaw, Northern Illinois University, and Argonne National Laboratory remained mostly unchanged. Again, we were delighted to receive enthusiastic responses from distinguished US and Polish scientists who were invited to p- ticipate.

This workshop includes about 110 papers describing the flux pinning and related electromagnetic phenomena in superconductors. Various problems are argued on exotic properties of flux lines, flux dynamics, flux pinning mechanisms, critical current density and critical state phenomena in both high- and low-temperature superconductors.

Research into high-Tc materials demands the co-operation of physicists, chemists and materials scientists to discover the best solutions to the most important challenges presented by the field. In the fifth annual Workshop on High Temperature Superconductors and Novel Inorganic Materials Engineering, the topic is extended beyond high-Tc superconductivity to include other advanced oxide materials, mainly colossal magnetoresistance materials, which are closely related to the ceramic superconductors. This book covers the synthesis, characterisation (both structural and physical) and engineering of this class of materials.

Superconductors offer high throughput with low electric losses and have the potential to transform the electric power grid. Transmission networks incorporating cables of this type could, for example, deliver more power and enable substantial energy savings. Superconductors in the Power Grid: Materials and Applications provides an overview of superconductors and their applications in power grids. Sections address the design and engineering of cable systems and fault current limiters and other emerging applications for superconductors in the power grid, as well as case studies of industrial applications of superconductors in the power grid. - Expert editor from highly respected US government-funded research centre - Unique focus on superconductors in the power grid - Comprehensive coverage

The book develops a comprehensive understanding of the surface impedance of the oxide high-temperature superconductors in comparison with the conventional superconductor Nb3Sn. Linear and nonlinear microwave responses are treated separately, both in terms of models, theories or numerical approaches and in terms of experimental results. The theoretical treatment connects fundamental aspects of superconductivity to the specific high-frequency properties. The experimental data review the state of the art, as reported by many international groups. The book describes further the main features of appropriate preparation, handling, mounting, and refrigeration techniques, and finally discusses possible applications in passive and active microwave devices.