Low temperature research has become fairly widespread in the country after the availability of closed cycle refrigerators. It is opportune to write a book for students and researchers in India on production of low temperatures and techniques for the measurement of physical properties of materials at such temperatures. This book is an effort in this direction. The first part of the book discusses methods for producing temperatures down to 1.8 K. There is a fairly extensive discussion on different types of closed cycle refrigerators. The behaviour of properties of materials relevant in Cryogenics is dealt with in some detail. Useful tips on construction of cryostats are given. Thermometry is discussed extensively. The second part of the book deals with digital measuring techniques. Details of experimental methods for measuring thermal and electrical properties, point contact tunneling, scanning probe microscopy, and noise at low temperatures are discussed. This part of the book is born out of the rich personal experience in such measurements of one of the authors (AKR). There is an appendix on vacuum techniques. The book can be used for teaching an elective course in Low Temperature Physics at the M.Sc. level. It will be useful for researchers in Low Temperature Physics.

The minimum temperature in the natural universe is 2.7 K. Laboratory refrigerators can reach temperatures in the microkelvin range. Modern industrial refrigerators cool foods at 200 K, whereas space mission payloads must be capable of working at temperatures as low as 20 K. Superconducting magnets used for NMR work at 4.2 K. Hence the properties of materials must be accurately known also at cryogenic temperatures. This book provides a guide for engineers, physicists, chemists, technicians who wish to approach the field of low-temperature material properties. The focus is on the thermal properties and a large spectrum of experimental cases is reported. The book presents updated tables of low-temperature data on materials and a thorough bibliography supplements any further research. Key Features include: ° Detailed technical description of experiments ° Description of the newest cryogenic apparatus ° Offers data on cryogenic properties of the latest new materials ° Current reference review

Most descriptions of polymers start at room temperature and end at the melting point. This textbook starts at very low temperatures and ends at room temperature. At low temperatures, may processes and relaxations are frozen which allows singular processes or separate relaxations to be studied. At room temperatures, or at the main glass transitions, many processes overlap and the properties are determined by relaxations. At low temperatures, there are temperature ranges with negligible influences by glass transitions. They can be used for investigating so-called basic properties which arise from principles of solid state physics. The chain structure of polymers, however, requires stringent modifications for establishing solid state physics of polymers. Several processes which are specific of polymers, occur only at low temperatures. There are also technological aspects for considering polymers at low temperatures. More and more applications of polymeric materials in low temperature technology appear. Some examples are thermal and electrical insulations, support elements for cryogenic devices, low-loss materials for high frequency equipments. It is hoped that, in addition to the scientific part, a data collection in the appendix may help to apply polymers more intensively in low temperature technology. The author greatly appreciates the contributions by his coworkers of the Kernforschungszentrum Karlsruhe in measurement and discussion of many data presented in the textbook and its appendix. Fruitful disccussions with the colleagues Prof. H. Baur, Prof. S. Hunklinger, Prof. D. Munz and Prof. R.

Publisher description

Cryogenics is the study of low temperature interactions - temperatures well below those existing in the natural universe. The book covers a large spectrum of experimental cases, including basic vacuum techniques, indispensable in cryogenics. Guidance in solving experimental problems and numerous numerical examples are given, as are examples of the applications of cryogenics in such areas as underground detectors and space applications. Updated tables of low-temperature data on materials are also presented, and the book is supplemented with a rich bibliography. Researchers (graduate and above) in the fields of physics, engineering and chemistry with an interest in the technology and applications of low-temperature measurements, will find this book invaluable. - Experiments described in technical detail - Description of newest cryogenic apparatus - Applications in multidisciplinary areas - Data on cryogenic properties of new materials - Current reference review

This work was begun quite some time ago at the University of Oxford during the tenure of an Overseas Scholarship of the Royal Commission for the Exhibition of 1851 and was completed at Banga lore when the author was being supported by a maintenance allowance from the CSIR Pool for unemployed scientists. It is hoped that significant developments taking place as late as the beginning of 1965 have been incorporated. The initial impetus and inspiration for the work came from Dr. K. Mendelssohn. To him and to Drs. R. W. Hill and N. E. Phillips, who went through the whole of the text, the author is obliged in more ways than one. For permission to use figures and other materials, grateful thanks are tendered to the concerned workers and institutions. The author is not so sanguine as to imagine that all technical and literary flaws have been weeded out. If others come across them, they may be charitably brought to the author's notice as proof that physics has become too vast to be comprehended by a single onlooker. E. S. RAJA GoPAL Department of Physics Indian Institute of Science Bangalore 12, India November 1965 v Contents Introduction ................................................................. .

This work covers the closely related areas of heat capacity, thermal expansion and elastic stiffness. It includes chapters on the fundamental principles and the observed behaviour of representative materials, such as cubic crystals, anisotropic solids, glasses, and polymers.

It has been almost thirty years since the publication of a book that is entirely dedicated to the theory, description, characterization and measurement of the thermal conductivity of solids. The recent discovery of new materials which possess more complex crystal structures and thus more complicated phonon scattering mechanisms have brought innovative challenges to the theory and experimental understanding of these new materials. With the development of new and novel solid materials and new measurement techniques, this book will serve as a current and extensive resource to the next generation researchers in the field of thermal conductivity. This book is a valuable resource for research groups and special topics courses (8-10 students), for 1st or 2nd year graduate level courses in Thermal Properties of Solids, special topics courses in Thermal Conductivity, Superconductors and Magnetic Materials, and to researchers in Thermoelectrics, Thermal Barrier Materials and Solid State Physics.

This book enables the reader to learn the fundamental and applied aspects of practical cryostat design by examining previous design choices and resulting cryostat performance. Through a series of extended case studies the book presents an overview of existing cryostat design covering a wide range of cryostat types and applications, including the magnet cryostats that comprise the majority of the Large Hadron Collider at CERN, space-borne cryostats containing sensors operating below 1 K, and large cryogenic liquid storage vessels. It starts with an introductory section on the principles of cryostat design including practical data and equations. This section is followed by a series of case studies on existing cryostats, describing the specific requirements of the cryostat, the challenges involved and the design choices made along with the resulting performance of the cryostat. The cryostat examples used in the studies are chosen to cover a broad range of cryostat applications and the authors of each case are leading experts in the field, most of whom participated in the design of the cryostats being described. The concluding chapter offers an overview of lessons learned and summarises some key hints and tips for practical cryostat design. The book will help the reader to expand their knowledge of many disciplines required for good cryostat design, including the cryogenic properties of materials, heat transfer and thermal insulation, instrumentation, safety, structures and seals.