This volume contains the lectures given at the Third Gordon Godfrey International Workshop on Computational Approaches to Novel Condensed Matter Systems which was held at The University of New South Wales July 12-17, 1993. Lecturers from Asia, Australia, Europe and North America gave a total of twenty-nine lectures which were spread over the five days. Unfortunately we were not able to include in this volume the lectures of S. Das Sarma from the University of Maryland on "Non-Equilibrium Growth as a Self-Organised Phenomenon" due to constraints of time. The workshops have been held annually since 1991 in Sydney, each covering a novel research area in condensed matter physics that is of topical interest. Australia has a strong tradition of research in condensed matter physics. The workshops are jointly organised by the School of Physics at the University of New South Wales (Sydney) and the Department of Theoretical Physics, Research School of Physical Sciences and Engineering at the Australian National University (Canberra). The late Gordon God frey was an Associate Professor of Physics at the University of New South Wales. He bequeathed his estate for the promotion and teaching of theoretical physics within the university. The primary purpose of each workshop is to expose post-graduate students in physics to both informal interaction and formal lectures from recognised international leaders in topical research areas. Past experience has demonstrated again and again that to be informed about a new field there is no substitute for personal contact and interaction."

This thesis examines a novel class of flexible electronic material with great potential for use in the construction of stretchable amplifiers and memory elements. Most remarkably the composite material produces spontaneous oscillations that increase in frequency when pressure is applied to it. In this way, the material mimics the excitatory response of pressure-sensing neurons in the human skin. The composites, formed of silicone and graphitic nanoparticles, were prepared in several allotropic forms and functionalized with naphthalene diimide molecules. A systematic study is presented of the negative differential resistance (NDR) region of the current-voltage curves, which is responsible for the material's active properties. This study was conducted as a function of temperature, graphite filling fraction, scaling to reveal the break-up of the samples into electric field domains at the onset of the NDR region, and an electric-field induced metal-insulator transition in graphite nanoparticles. The effect of molecular functionalization on the miscibility threshold and the current-voltage curves is demonstrated. Room-temperature and low-temperature measurements were performed on these composite films under strains using a remote-controlled, custom-made step motor bench.

The theory of stochastic processes provides a huge arsenal of methods suitable for analyzing the influence of noise on a wide range of systems. Noise-induced, noise-supported or noise-enhanced effects sometimes offer an explanation for as yet open problems (information transmission in the nervous system and information processing in the brain, processes at the cell level, enzymatic reactions, etc.), or pave the way to novel technological applications. Noise can play a prominent role in structure formation in physics, chemistry and biology, e.g. current filaments in semiconductors, catalytic reactions on surfaces, complex dynamics of the heart, brain, or of ecosystems. The book reviews those aspects of applied stochastics addressing researchers as well as students.

Little do we reliably know about the Mott transition, and we are far from a complete understanding of the metal --insulator transition due to electr- electron interactions. Mott summarized his basic ideas on the subject in his wonderful book Metal--Insulator nansitions that first appeared in 1974 11. 1). In his view, a Motk insulator displays a gap for charge-carrying excitations due to electron cowelations, whose importance is expressed by the presence of local magnetic moments regardless of whether or not they are ordered. Since the subject is far from being settled, different opinions on specific aspects of the Mott transition still persist. This book naturally embodies my own understanding of the phenomenon, inspired by the work of the late Sir Kevill Mott. The purpose of this book is twofold: first, to give a detailed presen- tion of the basic theoretical concopts for Mott insulators and, second, to test these ideas against the results from model calculations. For this purpose the Hubbard model and some of its derivatives are best suited. The Hubbard model describes a Mott transition with a mere minimum of tunable par- eters, and various exact statements and even exact solutions exist in certain limiting cases. Exact solutions not only allow us to test our basic ideas, but also help to assess the quality of approxin ate theories for correlated electron systems.

Advances in technology are demanding ever-increasing mastery over the materials being used: the challenge is to gain a better understanding of their behaviour, and more particularly of the relations between their microstructure and their macroscopic properties.

This work, of which this is the first volume, aims to provide the means by which this challenge may be met. Starting from the mechanics of deformation, it develops the laws governing macroscopic behaviour expressed as the constitutive equations always taking account of the physical phenomena which underlie rheological behaviour. The most recent developments are presented, in particular those concerning

heterogeneous materials such as metallic alloys, polymers and composites. Each chapter is devoted to one of the major classes of material behaviour.

As the subtitles indicate, Volume 1 deals with micro- and macroscopic constitutive behaviour and Volume 2 with damage and fracture mechanics. A third volume will be devoted to exercises and their full solutions complementing the content of these two first volumes.

Most of the chapters end with a set of exercises, to many of which either the full solution or hints on how to obtain this are given; each volume is profusely illustrated with explanatory diagrams and with electron-microscope photographs.

This book, now in its second edition, has been rigorously re-written, updated and modernised for a new generation. The authors improved the existing material, in particular in modifying the organisation, and added new up-to-date content. Understanding the subject matter requires a good knowledge of solid mechanics and materials science; the main elements of these fields are given in a set of annexes at the

end of the first volume. The authors also thought it interesting for the readers to give as footnotes some information about the many scientists whose names are attached to theories and formulae and whose memories must be celebrated.

Whilst the present book, as well as Volume 2, is addressed primarily to graduate students, part of it can be used in undergraduate courses; and it is hoped that practising engineers and scientists will find the information it conveys useful. It is the authors hope also that English-speaking readers will want to learn about the aspects of French

culture, and more particularly of the French school of micromechanics of materials, which this treatment undoubtedly displays.

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In this book, a new phenomenological approach to brittle medium fractu re initiation under shock pulses is developed. It provides an opportun ity to estimate fracture of media with and without macrodefects. A qua litative explanation is thus obtained for a number of principally impo rtant effects of high-speed dynamic fracture that cannot be clarified within the framework of previous approaches. It is possible to apply t his new strategy to resolve applied problems of disintegration, erosio n, and dynamic strength determination of structural materials. Special ists can use the methods described to determine critical characteristi cs of dynamic strength and optimal effective fracture conditions for r igid bodies. This book can also be used as a special educational cours e on deformation of materials and constructions, and fracture mechanic s.

"This book contains overviews on technologically important classes of glasses, their treatment to achieve desired properties, theoretical approaches for the description of structure-property relationships, and new concepts in the theoretical treatment of crystallization in glass-forming systems. It contains overviews about the state of the art and about specific features for the analysis and application of important classes of glass-forming systems, and describes new developments in theoretical interpretation by well-known glass scientists. Thus, the book offers comprehensive and abundant information that is difficult to come by or has not yet been made public." Edgar Dutra Zanotto (Center for Research, Technology and Education in Vitreous Materials, Brazil) Glass, written by a team of renowned researchers and experienced book authors in the field, presents general features of glasses and glass transitions. Different classes of glassforming systems, such as silicate glasses, metallic glasses, and polymers, are exemplified. In addition, the wide field of phase formation processes and their effect on glasses and their properties is studied both from a theoretical and experimental point of view.

Strain Effect in Semiconductors: Theory and Device Applications presents the fundamentals and applications of strain in semiconductors and semiconductor devices that is relevant for strain-enhanced advanced CMOS technology and strain-based piezoresistive MEMS transducers. Discusses relevant applications of strain while also focusing on the fundamental physics pertaining to bulk, planar, and scaled nano-devices. Hence, this book is relevant for current strained Si logic technology as well as for understanding the physics and scaling for future strained nano-scale devices.

Systems driven far from thermodynamic equilibrium can create dissipative structures through the spontaneous breaking of symmetries. A particularlyfascinating feature of these pattern-forming systems is their tendency toproduce spatially confined states. These localized wave packets can exist as propagating entities through space and/or time.

Various examples of suchsystems will be dealt with in this book, including localized states in fluids, chemical reactions on surfaces, neural networks, optical systems, granular systems, population models, and Bose-Einstein condensates.

This book should appeal to all physicists, mathematicians and electrical engineers interested in localization in far-from-equilibrium systems. The authors - all recognized experts in their fields -strive to achieve a balance between theoretical and experimental considerations thereby givingan overview offascinating physical principles, their manifestations in diverse systems, and the noveltechnical applications on the horizon.

This book mainly focuses on the investigation of the electric-field control of magnetism and spin-dependent transportation based on a Co40Fe40B20(CoFeB)/Pb(Mg1/3Nb2/3)0.7Ti0.3O3(PMN-PT) multiferroic heterostructure. Methods of characterization and analysis of the multiferroic properties with in situ electric fields are induced to detect the direct magnetoelectric (ME) coupling. A switchable and non-volatile electric field control of magnetization in CoFeB/PMN-PT(001) structures is observed at room temperature, and the mechanism of direct coupling between the ferroelectric domain and ferromagnetic film due to the combined action of 109 Degrees ferroelastic domain switching in PMN-PT and the absence of magnetocrystalline anisotropy in CoFeB is demonstrated. Moreover, the electric-field control of giant magnetoresistance is achieved in a CoFeB-based spin valve deposited on top of (011) oriented PMN-PT, which offers an avenue for implementing electric-writing and magnetic-reading random access memory at room temperature. Readers will learn the basic properties of multiferroic materials, many useful techniques related to characterizing multiferroics and the interesting ME effect in CoFeB/PMN-PT structures, which is significant for applications.

th Superconductivity occ upies as pecial, unique place in the 20 century physics. Just think ofi t: its microscopic mechanism was understood only in 1957-46years after the discovery of superconductivity in 1911. In contrast, thetheory ofnormal metals behavior (or, to be more precise, the theory of metals in normal state) wasformed as early as the twenties, immediately f ollowing the creation of quantum mechanics. Moreover, when I took up the theory of superconductivity in 1943, not only microscopic theory was non existent, but even macroscopic superconductivity theory was quiteincomplete. The problem is that the Londons equations, introduced in 1935, allow only aquantitative description ofsuperconductors in magneticf ields weak in comparison with the critical field. Also, even in weakfields, theLondons theory is strictly applicableonly to Type II superconductors-although the division ofsuperconductors into Type I and Type II materials was notsuggested until much later, in early 1950's. Asf ar as nonequilibrium phenomena are conc erned, then until 1943 the most remarkable, yet proved to be fault afterwards, implication was that ofa complete absence ofa ll thermoelectric effects in superconducting state.

The book you are now holding represents the final step in a long process for the editors and organizers of the Advanced Study Institute on hard magnetic materials. The editors interest in hard magnetic materials began in 1985 with an attempt to better understand the moments associated with the different iron sites in Nd Fe B. These 14 moments can be obtained from neutron diffraction studies, but we qUickly realized that iron-57 Mossbauer spectroscopy should lead to a better determination of these moments. However, it was also realized that the complex Mossbauer spectra obtained for these hard magnetic materials could not be easily understood without a broad knowledge of their various structural, electronic, and magnetic properties. Hence it seemed useful to the editors to bring together scientists and engineers to discuss, in a tutorial setting, the various properties of these and future hard magnetic materials. We believe the inclusion of engineers as well as scientists in these discussions was essential because the design of new magnetic materials depends very much upon the mode in which they are used in practical devices.

1. An Introductory Review.- 2. Fabrication Techniques for Submicron Devices.- 3. Heterojunctions and Interfaces.- 4. Semiclassical Carrier Transport Models.- 5. Transient Hot-Carrier Transport.- 6. Alloys and Superlattices.- 7. The Electron-Electron Interaction.- 8. Lateral Surface Superlattices.- 9. Quantum Transport in Small Structures.- 10. Noise in Submicron Devices.

An introduction and comprehensive survey of the main issues in mesosocopic physics. Topics covered include quantum Hall effects, transport through quantum wires and dots, coherence in mesoscopic systems, spintronics, disordered systems, and solid state quantum computation. Some contributions are dedicated to the connections between nanoscience and biophysics and quantum optics.
Although the topics mentioned have many aspects in common, they span a wide area of physics. It is therefore especially important to provide a broad view of this rapidly expanding field. Thanks to the excellent presentations, the book will be found suitable both for young researchers who want to enter the field and stimulating for more experienced scientists.

Topological defects are the subject of intensive studies in many different branches of physics ranging from cosmology to liquid crystals and from elementary particles to colloids and biological systems. Liquid crystals are fascinating materials which present a great variety of these mathematical objects and can therefore be considered as an extremely useful laboratory for topological defects. This book is the first attempt to present together complementary approaches to the investigations of topological defects in liquid crystals using theory, experiments and computer simulations.

Amorphous and nanocrystalline materials are a class of their own. Their properties are quite different to those of the corresponding crystalline materials. This book gives systematic insight into their physical properties, structure, behaviour, and design for special advanced applications. The book will appeal to researchers, research engineers and advanced students in materials science.

This book mainly focuses on the study of the high-temperature superconductor Bi2Sr2CaCu2O8+ (Bi2212) and single-layer FeSe film grown on SrTiO3 (STO) substrate by means of angle-resolved photoemission spectroscopy (ARPES). It provides the first electronic evidence for the origin of the anomalous high-temperature superconductivity in single-layer FeSe grown on SrTiO3 substrate. Two coexisted sharp-mode couplings have been identified in superconducting Bi2212. The first ARPES study on single-layer FeSe/STO films has provided key insights into the electronic origin of superconductivity in this system. A phase diagram and electronic indication of high Tc and insulator to superconductor crossover have been established in the single-layer FeSe/STO films. Readers will find essential information on the techniques used and interesting physical phenomena observed by ARPES.

The almost universal presence of water in our everyday lives and the very common' nature of its presence and properties possibly deflects attention from the fact that it has a number of very unusual characteristics which, furthermore, are found to be extremely sensitive to physical parameters, chemical environment and other influences. Hydrogen-bonding effects, too, are not restricted to water, so it is necessary to investigate other systems as well, in order to understand the characteristics in a wider context. Hydrogen Bond Networks reflects the diversity and relevance of water in subjects ranging from the fundamentals of condensed matter physics, through aspects of chemical reactivity to structure and function in biological systems.

This volume differs somewhat from the previous volumes in the series in that there is a strong emphasis on the physical aspects and not so much on the chemical aspects of intermetallic compounds. Two of the chapters are concerned with relatively new experimental methods of studying rare earth metallic phases - high energy neutron spectroscopy and light scattering. In these chapters the authors explain the new kinds of information one obtains from these techniques and how this complements the knowledge previously gleaned from the more common measurements - such as NMR, heat capacities, magnetic susceptibility, transport and elastic properties. One of the remaining three chapters deals with NMR studies of rare earth intermetallics and the final two chapters are concerned, not so much with a particular experimental technique, but with physical phenomena that occur in these compounds: the electron-phonon interaction and heavy fermion behavior.

Lectures and seminar talks review theory and experimental work concerning transport phenomena and the closely related quantum mechanics in 11 chapters covering preparation and characterization, coherence and dephasing, quantization of conductance, quantum Hall effect, persistent currents, quantum tr

The past three decades have been a period where useful current and voltage instabilities in solids have progressed from exciting research problems to a wide variety of commercially available devices. Materials and electronics research has led to devices such as the tunnel (Esaki) diode, transferred electron (Gunn) diode, avalanche diodes, real-space transfer devices, and the like. These structures have proven to be very important in the generation, amplification, switching, and processing of microwave signals up to frequencies exceeding 100 GHz. In this treatise we focus on a detailed theoretical understanding of devices of the kind that can be made unstable against circuit oscillations, large amplitude switching events, and in some cases, internal rearrangement of the electric field or current density distribution. The book is aimed at the semiconductor device physicist, engineer, and graduate student. A knowledge of solid state physics on an elementary or introductory level is assumed. Furthermore, we have geared the book to device engineers and physicists desirous of obtaining an understanding substantially deeper than that associated with a small signal equivalent circuit approach. We focus on both analytical and numerical treatment of specific device problems, concerning ourselves with the mechanism that determines the constitutive relation governing the device, the boundary conditions (contact effects), and the effect of the local circuit environment.

Statistical Physics bridges the properties of a macroscopic system and the microscopic behavior of its constituting particles, otherwise impossible due to the giant magnitude of Avogadro's number. Numerous systems of today's key technologies - such as semiconductors or lasers - are macroscopic quantum objects; only statistical physics allows for understanding their fundamentals. Therefore, this graduate text also focuses on particular applications such as the properties of electrons in solids with applications, and radiation thermodynamics and the greenhouse effect.

In recent years, III-V devices, integrated circuits, and superconducting integrated circuits have emerged as leading contenders for high-frequency and ultrahigh speed applications. GaAs MESFETs have been applied in microwave systems as low-noise and high-power amplifiers since the early 1970s, replacing silicon devices. The heterojunction high-electron-mobility transistor (HEMT), invented in 1980, has become a key component for satellite broadcasting receiver systems, serving as the ultra-low-noise device at 12 GHz. Furthermore, the heterojunction bipolar transistor (HBT) has been considered as having the highest switching speed and cutoff frequency in the semiconductor device field. Initially most of these devices were used for analog high-frequency applications, but there is also a strong need to develop high-speed III-V digital devices for computer, telecom munication, and instrumentation systems, to replace silicon high-speed devices, because of the switching-speed and power-dissipation limitations of silicon. The potential high speed and low power dissipation of digital integrated circuits using GaAs MESFET, HEMT, HBT, and superconducting Josephson junction devices has evoked tremendous competition in the race to develop such technology. A technology review shows that Japanese research institutes and companies have taken the lead in the development of these devices, and some integrated circuits have already been applied to supercomputers in Japan. The activities of Japanese research institutes and companies in the III-V and superconducting device fields have been superior for three reasons. First, bulk crystal growth, epitaxial growth, process, and design technology were developed at the same time."