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In this thesis, the author investigates hidden-order phase transition at T0 = 17.5 K in the heavy-fermion URu2Si2. The four-fold rotational symmetry breaking in the hidden order phase, which imposes a strong constraint on the theoretical model, is observed through the magnetic torque measurement. The translationally invariant phase with broken rotational symmetry is interpreted as meaning that the hidden-order phase is an electronic “nematic” phase. The observation of such nematicity in URu2Si2 indicates a ubiquitous nature among the strongly correlated electron systems.The author also studies the superconducting state of URu2Si2 below Tc = 1.4 K, which coexists with the hidden-order phase. A peculiar vortex penetration in the superconducting state is found, which may be related to the rotational symmetry breaking in the hidden-order phase. The author also identifies a vortex lattice melting transition. This transport study provides essential clues to the underlying issue of quasiparticle dynamics as to whether a quasiparticle Bloch state is realized in the periodic vortex lattice.

In this text experts review experimental studies that directly reveal the relationship between the atomic structure and physical behavior of high-Tc superconductors. The thorough discussion centers on twins, twin boundaries, the vortex lattice, and magnetic and mechanical properties in connection with structural imperfections. Particular attention is paid to the role of the oxygen atom in the Y-Ba-Cu-O and La-Cu-O species. The experimental methods evaluated include electron and X-ray diffraction, electron microscopy, and M|ssbauer spectroscopy. This book makes extraordinarily valuable data obtained at the Institute of Solid State Physics at Chernogolovka accessible to the wider international community of researchers in superconductivity.

High efficiency, large scale, stationary computing systems – supercomputers and data centers – are becoming increasingly important due to the movement of data storage and processing onto remote cloud servers. This book is dedicated to a technology particularly appropriate for this application – superconductive electronics, in particular, rapid single flux quantum circuits. The primary purpose of this book is to introduce and systematize recent developments in superconductive electronics into a cohesive whole to support the further development of large scale computing systems. A brief background into the physics of superconductivity and the operation of common superconductive devices is provided, followed by an introduction into different superconductive logic families, including the logic gates, interconnect, and bias current distribution. Synchronization, fabrication, and electronic design automation methodologies are presented, reviewing both widely established concepts and techniques as well as recent approaches. Issues related to memory, synchronization, interconnects, coupling noise, bias networks, signal interfaces, and deep scaling of superconductive structures and design for testability are described, and models, expressions, circuits, algorithms, and design methodologies are discussed and placed in context. The aim of this book is to provide insight and engineering intuition into the design of large scale digital superconductive circuits and systems.

This book offers a comprehensive survey of the latest research concerning high-entropy alloy (HEA) superconductors, an emerging topic which has attracted significant attention since their discovery in 2014. HEAs represent a novel class of materials introduced in 2004, renowned for their exceptional mechanical attributes, robust resistance to corrosion, and remarkable thermal stability, among other characteristics. Superconductivity has emerged as a particularly prominent subject in this domain. Recent important findings are robust superconductivity under extraordinarily high pressure or ion irradiation, possible unconventional superconductivity, enhancement of bulk superconductivity, and high critical current density. In this book, HEA superconductors are classified into two primary categories: The first class encompasses alloy systems characterized by body-centered cubic and hexagonal close-packed structures; and the second class comprises intermetallic types. In each of these classes, the authors expound upon the exotic properties, applications, and materials design, aligning with the overarching themes of their work. This book delivers a topical and timely discussion of superconductivity associated with the high-entropy state, the potential applications under consideration, and the intricacies of materials design. These recent discoveries are poised to captivate many researchers in materials science, particularly those engaged in high-entropy alloys and the realm of superconducting properties and technology.

This book presents experimental studies of nonequilibrium phase transitions induced by ac and dc forces in collectively interacting systems—a superconducting vortex system with random pinning. It first shows that a phase transition from reversible to irreversible flow occurs by increasing vortex density as well as amplitude of ac shear, which is indicative of the universality of the reversible-irreversible transition. Two distinct flow regimes are also found in the reversible phase. Next, the book presents new methods for dc driven experiments—transverse mode-locking and transverse current-voltage measurements—and provides convincing evidence of the second-order dynamical transition from disordered plastic to anisotropically ordered smectic flow. Lastly it reports on the first experimental demonstration of the Kibble-Zurek mechanism for the nonequilibrium phase transition.The experimental results indicate that both the reversible-irreversible transition and the dynamical ordering transition belong to the directed percolation universality class which is one of the fundamental classes of nonequilibrium phase transitions. Hence, the findings will be generalized to other nonequilibrium systems and stimulate research on nonequilibrium physics.

This book presents advances in the field of rare-earth (R) – transition metal (M) – boron compounds with extensive references. Since titanium and scandium do not form compounds with rare-earths, the Sc/Ti-M-B series are additionally presented. In each chapter the crystal structures, the complex physical properties as determined from neutron diffraction, magnetic measurements, resonance studies, transport properties and band structure calculations are critical analyzed. The models used in describing the experimental evidence are also presented. Tables with the main properties of the R-M-B compounds are given and representative data are illustrated in figures. In this way, the book provides state-of-the art knowledge and a valuable analysis of up-to-date results in the field. The technical applications, as permanent magnets, thermoelectric and magnetocaloric devices, hydrogen storage are also highlighted along with the authors insights into future directions in the field. The book is ofinterest for scientists involved in the development of the field as well as those working in the technical uses of rare-earth compounds.

This book presents comprehensive studies of charge density waves (CDW) in a high-Tc cuprate superconductor using x-ray scattering techniques under uniaxial pressure. Specifically, the work addresses inelastic x-ray scattering studies under uniaxial pressure performed on the underdoped cuprate YBa2Cu3O6.67(p=0.12, Tc=65K) with incoming photon energy in the resonant (E=931.3 eV, Cu-L3 edge) and non-resonant conditions (E=17.794 keV). This is a completely new approach to the investigation of charge density waves. It revealed new features of charge density waves in cuprates, whose properties had previously been inaccessible..

This book presents an overview of the science of superconducting materials. It covers the fundamentals and theories of superconductivity. Subjects of special interest involving mechanisms of high temperature superconductors, tunneling, transport properties, magnetic properties, critical states, vortex dynamics, etc. are present in the book. It assists as a fundamental resource on the developed methodologies and techniques involved in the synthesis, processing, and characterization of superconducting materials. The book covers numerous classes of superconducting materials including fullerenes, borides, pnictides or iron-based chalcogen superconductors ides, alloys and cuprate oxides. Their crystal structures and properties are described. Thereafter, the book focuses on the progress of the applications of superconducting materials into superconducting magnets, fusion reactors, and accelerators and other superconducting magnets. The applications also cover recent progress in superconducting wires, power generators, powerful energy storage devices, sensitive magnetometers, RF and microwave filters, fast fault current limiters, fast digital circuits, transport vehicles, and medical applications.

This book includes the synthesis, analysis and characterization of nanomaterials that are an important ingredient in nanotechnologies. Nanomaterials contain nanoparticles, smaller than 100 nanometers in at least one dimension. Nanomaterials are coming into use in health care, electronics, cosmetics and other areas. Their physical and chemical properties differ from those of bulk materials. This needs to cover health risks to workers and potential risks to environment. This is currently done on a case-by-case basis, but risk assessment methods need to be kept up to date as the use of nanomaterials expands, especially as they find their way into consumer products. This book covers the basics to advanced applications of nanomaterials and provides a useful resource for researchers and professionals in the field. ​

This book provides a modern introduction to the growth, characterization, and physics of iron-based superconducting thin films. Iron pnictide and iron chalcogenide compounds have become intensively studied key materials in condensed matter physics due to their potential for high temperature superconductivity. With maximum critical temperatures of around 60 K, the new superconductors rank first after the celebrated cuprates, and the latest announcements on ultrathin films promise even more. Thin film synthesis of these superconductors began in 2008 immediately after their discovery, and this growing research area has seen remarkable progress up to the present day, especially with regard to the iron chalcogenides FeSe and FeSe1-xTex, the iron pnictide BaFe2-xCoxAs2 and iron-oxyarsenides.This essential volume provides comprehensive, state-of-the-art coverage of iron-based superconducting thin films in topical chapters with detailed information on thin film synthesis and growth, analytical film characterization, interfaces, and various aspects on physics and materials properties. Current efforts towards technological applications and functional films are outlined and discussed. The development and latest results for monolayer FeSe films are also presented. This book serves as a key reference for students, lecturers, industry engineers, and academic researchers who would like to gain an overview of this complex and growing research area.

This book is on applied superconductivity, which is one of the topical issues of modern science and technology. At present, the prospects for the practical application of superconductivity are obvious from both economic and practical points of view. It can reduce heat losses and reduce the weight and size of equipment, improve the reliability of electrical devices and power systems, and create new devices. As a result, the achievements of applied superconductivity make it possible to perform effective retrofitting of equipment for scientific research, in medicine, electric power, electrical engineering, transport, and to introduce new advanced technologies that provide higher efficiency, significantly reducing working costs.

This book is indexed in Chemical Abstracts ServiceResearchers working at the frontier of high-Tc Superconductors have reviewed the development in this area in the past 20 years. Both experimental and theoretical aspects have been covered. New directions and possible theoretical models were suggested. The contributors of this book are from China Center of Advanced Science and Technology (CCAST); Institute of Physics Chinese Academy of Sciences (CAS); National Lab for Superconductivity, Institute of Physics, CAS; School of Physics, Peking University and Center of Advanced Study Tsinghua University.This volume will be a useful guide to those who are working in the field.

This compact undergraduate textbook provides a concise yet thorough introduction to the fundamentals of solid-state physics, while also briefly discussing the historical context surrounding key scholars in the field. The vivid explanations and unique didactic approach adopted in the book aim to generate interest in these subjects while also serving as a motivating primer and supporting companion for studying more detailed and advanced textbooks in solid-state physics. The book is also suitable as a quick refresher for students preparing for examinations. The third edition features many extensions, including an up-to-date discussion of topological materials, a rapidly developing area at the forefront of solid-state physics. Primarily concentrating on the electric and magnetic properties of materials, the book will benefit undergraduate students in the fields of physics, materials science, and electrical engineering.

This book provides a comprehensive and up-to-date description of the Josephson effect, a topic of never-ending interest in both fundamental and applied physics. In this volume, world-renowned experts present the unique aspects of the physics of the Josephson effect, resulting from the use of new materials, of hybrid architectures and from the possibility of realizing nanoscale junctions. These new experimental capabilities lead to systems where novel coherent phenomena and transport processes emerge. All this is of great relevance and impact, especially when combined with the didactic approach of the book. The reader will benefit from a general and modern view of coherent phenomena in weakly-coupled superconductors on a macroscopic scale. Topics that have been only recently discussed in specialized papers and in short reviews are described here for the first time and organized in a generalframework. An important section of the book is also devoted to applications, with focus on long-term, future applications. In addition to a significant number of illustrations, the book includes numerous tables for comparative studies on technical aspects.

This thesis presents analytical theoretical studies on the interplay between charge density waves (CDW) and superconductivity (SC) in the actively studied transition-metal dichalcogenide 1T-TiSe2. It begins by reapproaching a years-long debate over the nature of the phase transition to the commensurate CDW (CCDW) state and the role played by the intrinsic tendency towards excitonic condensation in this system. A Ginzburg-Landau phenomenological theory was subsequently developed to understand the experimentally observed transition from commensurate to incommensurate CDW (ICDW) order with doping or pressure, and the emergence of a superconducting dome that coexists with ICDW. Finally, to characterize microscopically the effects of the interplay between CDW and SC, the spectrum of CDW fluctuations beyond mean-field was studied in detail. In the aggregate, the work reported here provides an encompassing understanding of what are possibly key microscopic underpinnings of the CDWand SC physics in TiSe2.

This volume contains extended abstracts of the 10 plenary lectures, 27 invited symposium lectures and ap- proximately 300 contributed papers that were presented at the 25th Congress Ampère. The contributions cover the full range of magnetic resonance and radiospectroscopy and their applications in physics, chemical physics, medicine and biology. Advanced NMR and ESR techniques are treated, as are their applications to novel materials.

This new edition updates readers in three areas of NMR studies, namely, recent developments in high-Tc materials, heavy fermion systems and actinide oxides are presented. The NMR probe has yielded a vast array of data for solid state materials, corresponding to different compounds, ionic sites, and nuclear species, as well as to a wide variety of experimental conditions. The last two parts of the book are completely new in this edition, while the first part has seen major updates.This edition features the latest developments for high-Tc materials, especially the advances in the area of pseudogap studies are reviewed. An in depth overview of heavy fermion systems is presented in the second part, notably Kondo lattices, quantum critical points and unconventional superconductivity are areas of intense research recently and are covered extensively. Finally, valuable information from NMR studies with actinide oxides will be provided.Ongoing analysis and discussion of NMR data have resulted in a wealth of important insights into the physics of these exotic systems. The aims of this monograph are manyfold. First, it reviews NMR methodology as it has been applied to the different studies. This is addressed to NMR practitioners and to physics laypersons alike. Next, it presents a review of NMR measurements and the wide variety of phenomena which they represent. The third phase is to recount the theoretical model calculations and other proposals which have been put forward to account for these data.

This book reports on the development and application of a new uniaxial pressure apparatus that is currently generating considerable interest in the field of materials physics. The author provides practical guidelines for performing such experiments, backed up by finite element simulations. Subsequently, the book reports on two uses of the device. In the first, high pressures are used to tune to a Van Hove singularity in Sr2RuO4, while the effects on the unconventional superconductivity and the normal state properties are investigated. In the second experiment, precise and continuous strain control is used to probe symmetry breaking and novel phase formation in the vicinity of a quantum critical point in Sr3Ru2O7.

This book provides expert coverage of modern and novel aspects of the study of vortex matter, dynamics, and pinning in nanostructured and multi-component superconductors. Vortex matter in superconducting materials is a field of enormous beauty and intellectual challenge, which began with the theoretical prediction of vortices by A. Abrikosov (Nobel Laureate). Vortices, vortex dynamics, and pinning are key features in many of today's human endeavors: from the huge superconducting accelerating magnets and detectors at the Large Hadron Collider at CERN, which opened new windows of knowledge on the universe, to the tiny superconducting transceivers using Rapid Single Flux Quanta, which have opened a revolutionary means of communication.In recent years, two new features have added to the intrinsic beauty and complexity of the subject: nanostructured/nanoengineered superconductors, and the discovery of a range of new materials showing multi-component (multi-gap) superconductivity. In this book, leading researchers survey the most exciting and important recent developments in the field. Topics covered include: the use of scanning Hall probe microscopy to visualize interactions of a single vortex with pinning centers; Magneto-Optical Imaging for investigating what vortex avalanches are, why they appear, and how they can be controlled; and the vortex interactions responsible for the second magnetization peak. Other chapters discuss nanoengineered pinning centers of vortices for improved current-carrying capabilities, current anisotropy in cryomagnetic devices in relation to the pinning landscape, and the new physics associated with the discovery of new superconducting materials with multi-component superconductivity. The book offers something for almost everybody interested in the field: from experimental techniques to visualize vortices and study their dynamics, to a state-of-the-art theoretical microscopic approach to multicomponent superconductivity.

This thesis sheds important new light on the puzzling properties of Strontium Ruthenate. Using a sophisticated weak-coupling approach, exact within certain limits, it shows that proper treatment of spin-orbit and multi-band effects is crucial to the physics. Based on the results of these calculations, it resolves a crucial, long-standing puzzle in the field: It demonstrates why the experimentally observed time-reversal breaking is not incompatible with the observed lack of measurable edge currents. Lastly, the thesis makes predictions for the properties of the material under uniaxial strain, which are in good agreement with recent experiments —resolving the mystery of the so-called 3K phase, and suggesting the intriguing possibility that under strain the superconductor may become conventional.

This book proposes a thorough introduction for a varied audience. The reader will master London theory and the Pippard equations, and go on to understand type I and type II superconductors (their thermodynamics, magnetic properties, vortex dynamics, current transport…), Cooper pairs and the results of BCS theory. By studying coherence and flux quantization he or she will be lead to the Josephson effect which, with the SQUID, is a good example of the applications. The reader can make up for any gaps in his knowledge with the use of the appendices, follow the logic behind each model, and assimilate completely the underlying concepts. Approximately 250 illustrations help in developing a thorough understanding. This volume is aimed towards masters and doctoral students, as well as advanced undergraduates, teachers and researchers at all levels coming from a broad range of subjects (chemistry, physics, mechanical and electrical engineering, materials science…). Engineers workingin industry will have a useful introduction to other more applied or specialized material. Philippe Mangin is emeritus professor of physics at Mines Nancy Graduate School of Science, Engineering and Management of the University of Lorraine, and researcher at the Jean Lamour Institute in France. He is the former director of both the French neutron scattering facility, Léon Brillouin Laboratory in Orsay, and the Material Physics Laboratory in Nancy, and has taught superconductivity to a broad audience, in particular to engineering students. Rémi Kahn is a retired senior research scientist of the French Alternative Energies and Atomic Energy Commission (CEA-Saclay). He worked at the Léon Brillouin Laboratory and was in charge of the experimental areas of INB 101 (the Orphée research reactor). This work responded to the need to bring an accessible account suitable for a wide spectrum of scientists and engineers.

This thesis explores thermal transport in selected rare-earth-based intermetallic compounds to answer questions of great current interest. It also sheds light on the interplay of Kondo physics and Fermi surface changes. By performing thermal conductivity and electrical resistivity measurements at temperatures as low as 25mK, the author demonstrates that the Wiedemann–Franz law, a cornerstone of metal physics, is violated at precisely the magnetic-field-induced quantum critical point of the heavy-fermion metal YbRh2Si2. This first-ever observation of a violation has dramatic consequences, as it implies a breakdown of the quasiparticle picture. Utilizing an innovative technique to measure low-temperature thermal transport isothermally as a function of the magnetic field, the thesis interprets specific, partly newly discovered, high-field transitions in CeRu2Si2 and YbRh2Si2 as Lifshitz transitions related to a change in the Fermi surface. Lastly, by applying this new technique to thermal conductivity measurements of the skutterudite superconductor LaPt4Ge12, the thesis proves that the system is a conventional superconductor with a single energy gap. Thus, it refutes the widespread speculations about unconventional Cooper pairing in this material.

The purpose of this book is to provide an elementary yet systematic description of the Bogoliubov-de Gennes (BdG) equations, their unique symmetry properties and their relation to Green's function theory. Specifically, it introduces readers to the supercell technique for the solutions of the BdG equations, as well as other related techniques for more rapidly solving the equations in practical applications.The BdG equations are derived from a microscopic model Hamiltonian with an effective pairing interaction and fully capture the local electronic structure through self-consistent solutions via exact diagonalization. This approach has been successfully generalized to study many aspects of conventional and unconventional superconductors with inhomogeneities – including defects, disorder or the presence of a magnetic field – and becomes an even more attractive choice when the first-principles information of a typical superconductor is incorporated via the construction of a low-energy tight-binding model. Further, the lattice BdG approach is essential when theoretical results for local electronic states around such defects are compared with the scanning tunneling microscopy measurements.Altogether, these lectures provide a timely primer for graduate students and non-specialist researchers, while also offering a useful reference guide for experts in the field.

This undergraduate textbook provides an introduction to the fundamentals of solid state physics, including a description of the key people in the field and the historic context. The book concentrates on the electric and magnetic properties of materials. It is written for students up to the bachelor level in the fields of physics, materials science, and electric engineering. Because of its vivid explanations and its didactic approach, it can also serve as a motivating pre-stage and supporting companion in the study of the established and more detailed textbooks of solid state physics. The textbook is suitable for a quick repetition prior to examinations. This second edition is extended considerably by detailed mathematical treatments in many chapters, as well as extensive coverage of magnetic impurities.

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

This wide-ranging presentation of applied superconductivity, from fundamentals and materials right up to the details of many applications, is an essential reference for physicists and engineers in academic research as well as in industry. Readers looking for a comprehensive overview on basic effects related to superconductivity and superconducting materials will expand their knowledge and understanding of both low and high Tc superconductors with respect to their application. Technology, preparation and characterization are covered for bulk, single crystals, thins fi lms as well as electronic devices, wires and tapes. The main benefit of this work lies in its broad coverage of significant applications in magnets, power engineering, electronics, sensors and quantum metrology. The reader will find information on superconducting magnets for diverse applications like particle physics, fusion research, medicine, and biomagnetism as well as materials processing. SQUIDs and their usage in medicine or geophysics arethoroughly covered, as are superconducting radiation and particle detectors, aspects on superconductor digital electronics, leading readers to quantum computing and new devices.

In the second half of the last century solid state physics and materials science experienced a great advance and established itself as an important and independent new field.This book provides an introduction to the fundamentals of solid state physics, including a description of the key people in the field and the historic context. The book concentrates on the electric and magnetic properties of materials. It is written for students up to the bachelor in the fields of physics, materials science and electric engineering. Because of its vivid explanations and its didactic approach, it can also serve as a motivating pre-stage and supporting companion in the study of the established and more detailed textbooks of solid state physics. The book is suitable for a quick repetition prior to examinations.For his scientific accomplishments, in 1992 the author received the Max-Planck Research Price and in 2001 the Cryogenics Price. He studied physics and mathematics at the University of Marburg, as well at the Technical Universities of Munich and Darmstadt. In 1958 he obtained his PhD in experimental physics at the University of Marburg. After working at the Research Center Karlsruhe and at a research institute near Albany, New York, he worked for 12 years at the Argonne National Laboratory near Chicago, Illinois. In 1974 he accepted an appointment at a chair of Experimental Physics at the University of Tübingen. There he taught and performed research until his retirement in 1999.

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.

The book introduces scientists and graduate students to superconductivity, and highlights the differences arising from the different dimensionality of the sample under study. It focuses on transport in one-dimensional superconductors, describing relevant theories with particular emphasis on experimental results. It closely relates these results to the emergence of various novel fabrication techniques. The book closes by discussing future perspectives, and the connection and relevance to other physical systems, including superfluidity, Bose-Einstein condensates, and possibly cosmic strings.

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.

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.

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.

This book is about the work of 10 great scientists; who they were and are, their personal background and how they achieved their outstanding results and took their prominent place in science history. We follow one of physics and science history's most enigmatic phenomena, superconductivity, through 100 years, from its discovery in 1911 to the present, not as a history book in the usual sense, but through close ups of the leading characters and their role in that story, the Nobel laureates, who were still among us in the years 2001-2004 when the main round of interviews was carried out. Since then two of them already passed away. For each one of the 10 laureates, the author tells their story by direct quotation from interviews in their own words. Each chapter treats one laureate. The author first gives a brief account of the laureates'scientific background and main contribution. Then each laureate tells his own story in his own words. This book is unique in its approach to science history.

The physics of vortices in classical fluids has been a highly important subject for many years, both in fundamental science and in engineering applications. About 50 years ago, vortices started to become prominent as quantum me­ chanical objects constructed from a macroscopic wavefunction. Here the key developments are associated with the names R. Feynman, L. Onsager, L. D. Landau, F. London, V.L. Ginzburg and A.A. Abrikosov. Recently, the physics of vortices has undergone a further important step of diversification, namely in unconventional superconductors and superfluids, which are characterized by an anisotropic and/or spatially complex order parameter. It is this latest evolutionary step of vortex physics that is addressed in this book. The indi­ vidual chapters are concerned with the microscopic structure and dynamics of vortices in diverse systems ranging from superfluids and superconductors to neutron stars. Each of the 20 chapters is written by one or more experts on the parti­ cular subject. Each chapter provides an introduction and overview, empha­ sizing theoretical as well as experimental work, and includes references to both recent and pioneering earlier developments. In this way non-expert rea­ ders will also benefit from these lecture notes. Hence, the book will be useful for all researchers and graduate students interested in the physics of vorti­ ces in unconventional superconductors and superfluids. It may also serve as supplementary material for a graduate course on low-temperature solid-state physics.

The first edition of this book provided an introduction to the many static and dynamic features of magnetic flux structures in what are now called classical or low-temperature superconductors. It went out of print not long after the discovery of high-temperature superconductors in 1986 by J.G. Bednorz and K.A. Miiller, a discovery which resulted worldwide in an explosive growth of research and development in the field of superconductivity. Because of this upsurge of activities, a strong demand for this book clearly continued. Since the contents of the fourteen chapters of the first edition are still valid and continue to represent a useful introduction into the various subjects, it was felt that a reprinting of these chapters in this second edition would be highly attractive. In this way, the reader is also able to trace the earlier scienti­ fic developments, themselves constituting important ideas sometimes forgot­ ten by the new community dealing with high-temperature superconductivity. However, because of the exciting and important recent progress in the field of high-temperature superconductivity, an extensive chapter has been added in this second edition. It provides a summary of the new developments and a discussion of the highlights. Here keywords such as vortex matter, vortex imaging, and half-integer magnetic flux quanta describe surprising new issues.

This thesis combines highly accurate optical spectroscopy data on the recently discovered iron-based high-temperature superconductors with an incisive theoretical analysis. Three outstanding results are reported: (1) The superconductivity-induced modification of the far-infrared conductivity of an iron arsenide with minimal chemical disorder is quantitatively described by means of a strong-coupling theory for spin fluctuation mediated Cooper pairing. The formalism developed in this thesis also describes prior spectroscopic data on more disordered compounds. (2) The same materials exhibit a sharp superconductivity-induced anomaly for photon energies around 2.5 eV, two orders of magnitude larger than the superconducting energy gap. The author provides a qualitative interpretation of this unprecedented observation, which is based on the multiband nature of the superconducting state. (3) The thesis also develops a comprehensive description of a superconducting, yet optically transparent iron chalcogenide compound. The author shows that this highly unusual behavior can be explained as a result of the nanoscopic coexistence of insulating and superconducting phases, and he uses a combination of two complementary experimental methods - scanning near-field optical microscopy and low-energy muon spin rotation - to directly image the phase coexistence and quantitatively determine the phase composition. These data have important implications for the interpretation of data from other experimental probes.

Superconductors, Surfaces and Superlattices

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.

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.

The authors of this book present current research in the study of superconductivity. Topics discussed in this compilation include the effects of non-magnetic defects in hole doped cuprates; deep cryogenic refrigeration by photons based on the phonon deficit effect in superconductors; superconductivity driven by an anti-polar electric phase in high temperature superconducting materials; superconductive graphite intercalation compounds; a superconducting magnetic field concentrator with nanodimensional branches and slits; magnetic mechanisms of pairing in a strongly correlated electron system of copper oxides; two non-linear mechanisms of correlations between copper carriers in superconductivity and their microscopical descriptions; three dimensionality of the critical state and variational methods for magnetically anisotropic superconductors; theory of multi-band superconductivity; conserving approximation for the self-energy of the t-U-V-J model beyond the Hartree-Fock approximation; and superconductivity as a consequence of an ordering of zero-point oscillations in electron gas.

High-temperature superconductivity has transformed the landscape of solid state science, leading to the discovery of new classes of materials, states of matter, and concepts. However, despite being over a quarter of a century since its discovery, there is still no single accepted theory to explain its origin. This book presents one approach, the strong-coupling or bipolaron theory, which proposes that high-temperature superconductivity originates from competing Coulomb and electron-phonon interactions. The author provides a thorough overview of the theory, describing numerous experimental observations, and giving detailed mathematical derivations of key theoretical findings at an accessible level. Applications of the theory to existing high-temperature superconductors are discussed, as well as possibilities of liquid superconductors and higher critical temperatures. Alternative theories are also examined to provide a balanced and informative perspective. This monograph will appeal to advanced researchers and academics in the fields of condensed matter physics and quantum-field theories.

With contributions by numerous experts

Phase separation has become a fascinating subject in the discussion of cuprate superconductors. All these materials have layered structures containing CU02 planes as the most important building blocks. They are coupled only weakly so that the electronic properties show a nearly two-dimensional behaviour. Due to correlations the undoped compounds are insulators of the Mott­ Hubbard type exhibiting long-range antiferromagnetic order. Upon doping a rich scenario of physical phenomena appears: Even at low hole concentra­ tions the antiferromagnetic ordering temperature is reduced drastically and spin-glass behaviour as well as a hopping type conductivity can be observed. Further doping leads to metallic-like conductivity and below Tc to super­ conductivity. In this doping regime antiferromagnetic fluctuations are still observed. At very high charge carrier densities superconductivity is lost and the systems show pure metallic conduction without,magnetic correlations. One of the most interesting phenomena in high-T c research is the interplay between magnetism and conductivity or superconductivity. Especially the behaviour of charge carriers in the antiferromagnetic background raises a number of open questions. Two scenarios become possible: the carriers tend to delocalize over the whole crystal forming a homogeneous state with band-like structure or they separate into hole-rich (conducting, superconducting) and hole-poor (insulating, antiferromagnetic) phases leading to an inhomogeneous structure.

This new book compiles biographical sketches of top professionals in the fields of superconductivity and condensed matter, as well as research summaries from a number of different focuses in this important field. (Imprint: Nova Press)

Superconductivity has undergone tremendous advances in recent years. Most notable of course was the discovery of high temperature superconductivity in the cuprates. This discovery resulted in an enormous influx of new workers to the field representing a host of experimental and theoretical disciplines. When we combine this with the discovery of superconductivity in other materials such as heavy-fermion metals, MgB2, various organics, fullerenes, field-effect devices, magnetic metals under pressure, and presumably non s-symmetry triplet Cooper-pairing in ruthenates (e. g. Sr2Ru04) we have an enrichment of the phenomena superconductivity. This resulted in an explosion of interest in the field. Many of the new superconductors are being called unconventional, either with respect to the pairing mechanism or the symmetry of the under­ lying order parameter. Yet in spite of these new materials and directions, continuing studies of conventional electron-phonon based superconductivity remain interesting. With the aid of historical hindsight, we expect the field to continue to advance in unexpected directions. Nonetheless it is our view that a state of the art treatise on superconductivity is justified at this time, not only to summarize the present understanding, but also to introduce newcomers to the field, as was the case with the two justly-famous 1968'bibles of super­ conductivity'by our former colleague R. D. Parks for an earlier generation. Hopefully the present books might help to point the way for future workers, research and discoveries.

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 testsof 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 Novel Mechanisms of Superconductivity Conference was initially conceived in the early part of 1986 as a small, 2-1/2 day workshop of 40-70 scientists, both theorists and experimentalists interested in exploring the possible evidence for exotic, non phononic superconductivity. Of course, the historic discoveries of high temperature oxide superconductors by Bednorz and Mftller and the subsequent enhancements by the Houston/Alabama groups made such a small conference impractical. The conference necessarily had to expand, 2-1/2 days became 4-1/2 days and superconductivity in the high Tc oxides became the largest single topic in the workshop. In fact, this conference became the first major conference on this topic and thus, these proceedings are also the first maj or publication. However, heavy fermion, organic and low carrier concentration superconductors remained a very important part of this workshop and articles by the leaders in these fields are included in these proceedings. Ultimately the workshop hosted rearly 400 scientists, students and media including representatives from the maj or research groups in the U.S., Europe, Japan and the Soviet Union.

High temperature superconductivity is still one of the most discussed topicsin physics.'The Physics and Chemistry of Oxide Superconductors'collects together more than one hundred original contributions presented during the 2nd International Symposium of the Institute for Solid State Physics of the University of Tokyo. The main topics cover new insights into the basic mechanism of high temperature superconductivity, recent developments of new superconducting materials, the state of the art of thin film production,theoretical understanding of the electronic structures in this kind of material, theories for strongly correlated electron systems, and many physical and chemical effects.

'High-Tc Superconductivity'is based on a meeting held in Kiev and contains contributions discussing the most recent achievements in this field. The book includes reviews and original papers covering theoretical and experimental aspects of the subject. Keywords: electronic and magnetic properties, metallization processes, emission and optic spectra, lavitation, pinning, frustration and fluctuations, thin films