Cryogenics, a term commonly used to refer to very low temperatures, had its beginning in the latter half of the 19th century. Traditionally, this field is separated from Cryogenic Engineering and Low Temperature Physics (LTP). Cryogenic engineering is concerned with the design and development of low-temperature systems and components, while low temperature physics is more related to the fundamental research of material or fluid properties. This book discusses some recent findings and developments as well as gives an outlook on the fields of helium cryogenics and LTP. The main focus will be given to the helium cryogenics, though a smaller review is also presented for the fields of cryogenic energy storage facilities. Some future trends and R&D activities are also discussed. To orient the reader, the first four chapters are related to LTP, while the major part of the book is then devoted to helium cryogenics, for example, refrigeration techniques, cryostats, low temperature electronics, safety, etc.It should be particularly suited for advanced students, young researchers or engineers, who are intending to proceed with careers in helium cryogenics or LTP. However, the authors believe that the book will also be of value to experienced scientists, since it describes several very recent advances in experimental low temperature physics and technology, for example, ultra-low temperature technique and thermometry, as well as progress in helium cryogenics, such as heat transfer, cryostat designs for large facilities, and refrigerator developments. Extensive references are provided for the readers interested in the details of the cryogenic engineering advances. And last but not least, the authors hope that this book will widen the horizons of many without a solid state background, but with a general interest in low temperature physics and helium cryogenics.In attempting to cover such a wide field, a large degree of selection has been necessary, as complete volumes have been written on many topics which here have had to be covered in very few pages or less. It is inevitable that not everyone will agree with the present choice, especially if it is their own subject which has been discussed very briefly or not mentioned at all, and the editor accepts full responsibility for the selections made. The book is written at a level which should be followed by a university graduate in science or engineering, although, if their background has not included a course in cryogenic engineering, general or solid-state physics, some groundwork may be lacking.

The topic of lattice quantum spin systems (or 'spin systems' for short) is a f- cinating branch of theoretical physics and one of great pedigree, although many importantquestionsstillremaintobeanswered. The'spins'areatomic-sizedm- netsthatarelocalisedtopointsonalatticeandtheyinteractviathelawsofquantum mechanics. Thisintrinsicquantummechanicalnatureandthelarge(usuallyeff- tivelyin nite)numberofspinsleadstostrikingresultswhichcanbequitedifferent fromclassicalresultsandareoftenunexpectedandindeedcounter-intuitive. Spinsystemsconstitutethebasicmodelsofquantummagneticinsulatorsandso arerelevanttoawholehostofmagneticmaterials. Furthermore,theyareimportant asprototypicalmodelsofquantumsystemsbecausetheyareconceptuallysimple and yet stilldemonstrate surprisingly rich physics. Low dimensional systems, in 2Dandespecially1D,havebeenparticularlyfruitfulbecausetheirsimplicityhas enabledexactsolutionstobefoundwhichstillcontainmanyhighlynon-trivialf- tures. Spinsystemsoftendemonstratephasetransitionsandsowecanusethemto studytheinterplayofthermalandquantum uctuationsindrivingsuchtransitions. Ofcoursetherearemanycasesinwhichwecan ndnoexactsolutionandinthese casestheycanbeusedasatestinggroundforapproximatemethodsofmodern-day quantummechanics. Thesequantumsystemsthusprovideagreatvarietyofint- estinganddif cultchallengestothemathematicianorphysicalscientist. Thisbookwaspromptedbyaseriesoftalksgivenbyoneoftheauthors(JBP)at asummerschoolinJyvaskyla,Finland. Thesetalksprovidedadetailedviewofhow onegoesaboutsolvingthebasicproblemsinvolvedintreatingandunderstanding spinssystemsatzerotemperature. Itwasthislevelofdetail,missingfromothertexts inthearea,thatpromptedtheotherauthor(DJJF)tosuggestthattheselecturesbe broughttogetherwithsupplementarymaterialinordertoprovideadetailedguide whichmightbeofuse,perhapstoagraduatestudentstartingworkinthisarea. Thebookisorganisedintochaptersthatdeal rstlywiththenatureofquantum mechanicalspinsandtheirinteractions. Thefollowingchaptersthengiveadetailed guidetothesolutionoftheHeisenbergandXYmodelsatzerotemperatureusing theBetheAnsatzandtheJordan-Wignertransformation,respectively. Approximate methodsarethenconsideredfromChap. 7onwards,dealingwithspin-wavet- oryandnumericalmethods(suchasexactdiagonalisationsandMonteCarlo). The coupledclustermethod(CCM),apowerfultechniquethathasonlyrecentlybeen vii viii Preface appliedtospinsystemsisdescribedinsomedetail. The nalchapterdescribesother work,someofitveryrecent,toshowsomeofthedirectionsinwhichstudyofthese systemshasdeveloped. Theaimofthetextistoprovideastraightforwardandpracticalaccountofall of the steps involved in applying many of the methods used for spins systems, especiallywherethisrelatestoexactsolutionsforin nitenumbersofspinsatzero temperature. Inthisway,wehopetoprovidethereaderwithinsightintothesubtle natureofquantumspinproblems. Manchester,UK JohnB. Parkinson January2010 DamianJ. J. Farnell Contents 1 Introduction ...1 References...5 2 Spin Models...7 2. 1 SpinAngularMomentum...7 2. 2 CoupledSpins...10 1 2. 3 TwoInteractingSpin- 'areatomic-sizedm- netsthatarelocalisedtopointsonalatticeandtheyinteractviathelawsofquantum mechanics. Thisintrinsicquantummechanicalnatureandthelarge(usuallyeff- tivelyin nite)numberofspinsleadstostrikingresultswhichcanbequitedifferent fromclassicalresultsandareoftenunexpectedandindeedcounter-intuitive. Spinsystemsconstitutethebasicmodelsofquantummagneticinsulatorsandso arerelevanttoawholehostofmagneticmaterials. Furthermore,theyareimportant asprototypicalmodelsofquantumsystemsbecausetheyareconceptuallysimple and yet stilldemonstrate surprisingly rich physics. Low dimensional systems, in 2Dandespecially1D,havebeenparticularlyfruitfulbecausetheirsimplicityhas enabledexactsolutionstobefoundwhichstillcontainmanyhighlynon-trivialf- tures. Spinsystemsoftendemonstratephasetransitionsandsowecanusethemto studytheinterplayofthermalandquantum uctuationsindrivingsuchtransitions. Ofcoursetherearemanycasesinwhichwecan ndnoexactsolutionandinthese casestheycanbeusedasatestinggroundforapproximatemethodsofmodern-day quantummechanics. Thesequantumsystemsthusprovideagreatvarietyofint- estinganddif cultchallengestothemathematicianorphysicalscientist. Thisbookwaspromptedbyaseriesoftalksgivenbyoneoftheauthors(JBP)at asummerschoolinJyvaskyla,Finland. Thesetalksprovidedadetailedviewofhow onegoesaboutsolvingthebasicproblemsinvolvedintreatingandunderstanding spinssystemsatzerotemperature. Itwasthislevelofdetail,missingfromothertexts inthearea,thatpromptedtheotherauthor(DJJF)tosuggestthattheselecturesbe broughttogetherwithsupplementarymaterialinordertoprovideadetailedguide whichmightbeofuse,perhapstoagraduatestudentstartingworkinthisarea. Thebookisorganisedintochaptersthatdeal rstlywiththenatureofquantum mechanicalspinsandtheirinteractions. Thefollowingchaptersthengiveadetailed guidetothesolutionoftheHeisenbergandXYmodelsatzerotemperatureusing theBetheAnsatzandtheJordan-Wignertransformation,respectively. Approximate methodsarethenconsideredfromChap. 7onwards,dealingwithspin-wavet- oryandnumericalmethods(suchasexactdiagonalisationsandMonteCarlo). The coupledclustermethod(CCM),apowerfultechniquethathasonlyrecentlybeen vii viii Preface appliedtospinsystemsisdescribedinsomedetail. The nalchapterdescribesother work,someofitveryrecent,toshowsomeofthedirectionsinwhichstudyofthese systemshasdeveloped. Theaimofthetextistoprovideastraightforwardandpracticalaccountofall of the steps involved in applying many of the methods used for spins systems, especiallywherethisrelatestoexactsolutionsforin nitenumbersofspinsatzero temperature. Inthisway,wehopetoprovidethereaderwithinsightintothesubtle natureofquantumspinproblems. Manchester,UK JohnB. Parkinson January2010 DamianJ. J. Farnell Contents 1 Introduction ...1 References...5 2 Spin Models...7 2. 1 SpinAngularMomentum...7 2. 2 CoupledSpins...10 1 2. 3 TwoInteractingSpin- 's...11 2 2. 4 CommutatorsandQuantumNumbers...14 2. 5 PhysicalPicture...16 2. 6 In niteArraysofSpins...16 1 2. 7 1DHeisenbergChainwith S = andNearest-Neighbour 2 Interaction...18 References...19 1 3 Quantum Treatment of the Spin- Chain...21 2 3. 1 GeneralRemarks...21 3. 2 AlignedState...22 3. 3 SingleDeviationStates...23 3. 4 TwoDeviationStates...27 3. 4. 1 FormoftheStates ...33 3. 5 ThreeDeviationStates...36 Z N 3. 5. 1 BetheAnsatzforS = ?3...36 T 2 3. 6 StateswithanArbitraryNumberofDeviations...37 Reference...38 4 The Antiferromagnetic Ground State ...39 4. 1 TheFundamentalIntegralEquation...39 4. 2 SolutionoftheFundamentalIntegralEquation...43 4. 3 TheGroundStateEnergy...45 References...47 ix x Contents 5 Antiferromagnetic Spin Waves ...49 5. 1 TheBasicFormalism ...49 5. 2 MagneticFieldBehaviour ...

Cold and ultracold collisions occupy a strategic position at the intersection of several powerful themes of current research in chemical physics, in atomic, molecular and optical physics, and even in condensed matter. The nature of these collisions has important consequences for optical manipulation of inelastic and reactive processes, precision measurement of molecular and atomic properties, matter-wave coherences and quantum-statistical condensates of dilute, weakly interacting atoms. This crucial position explains the wide interest and explosive growth of the field since its inception in 1987. The author reviews elements of the quantum theory of scattering theory, collisions taking place in the presence of one or more light fields, and collisions in the dark, below the photon recoil limit imposed by the presence of any light field. Finally, it reviews the essential properties of these mesoscopic quantum systems and describes the key importance of the scattering length to condensate stability.

A comprehensive study of refrigeration from its beginnings in America up to 1950, which shows its relation to our national development, records the main trends in technological progress, describes the use of refrigeration, and gives some indication of its social effects. Originally published in 1953. The Princeton Legacy Library uses the latest print-on-demand technology to again make available previously out-of-print books from the distinguished backlist of Princeton University Press. These editions preserve the original texts of these important books while presenting them in durable paperback and hardcover editions. The goal of the Princeton Legacy Library is to vastly increase access to the rich scholarly heritage found in the thousands of books published by Princeton University Press since its founding in 1905.

A comprehensive study of refrigeration from its beginnings in America up to 1950, which shows its relation to our national development, records the main trends in technological progress, describes the use of refrigeration, and gives some indication of its social effects. Originally published in 1953. The Princeton Legacy Library uses the latest print-on-demand technology to again make available previously out-of-print books from the distinguished backlist of Princeton University Press. These editions preserve the original texts of these important books while presenting them in durable paperback and hardcover editions. The goal of the Princeton Legacy Library is to vastly increase access to the rich scholarly heritage found in the thousands of books published by Princeton University Press since its founding in 1905.

Being a Scientist is a comprehensive introduction to the many aspects of scientific life beyond the classroom and laboratory. Written with undergraduate science majors in mind, the book covers ethics, the philosophical bases of scientific methods, library research, reading, peer review, creativity, proposal and paper writing, and oral and poster presentations. In contrast to other texts in the field, which often take a simple prescriptive approach to these topics, Being a Scientist connects them to the historical and philosophical roots of modern science, as well as the common experiences of all people. Written in a conversational style, the book makes use of metaphor, historical anecdote, and hypothetical research about everyday household questions. This approach helps undergraduates learn basic research skills without being too intimidated by the advanced concepts, vocabulary, and methods which are encountered in looking at the current scientific literature. Being a Scientist is a textbook for a semester-long course devoted to teaching research and communication skills to undergraduate science majors, but it can be adapted for use in summer research experiences, capstone research courses, and other courses throughout the undergraduate curriculum.

Der Begriff des "horror vacui" umschlieBt die ganze Summe der Erkenntnis, welche die Alten auf einem Gebiet der Natur wissenschaft besaBen, in dem in den letzten J ahren Entdeckungen von auBerordentllcher Bedeutung gemacht worden sind. 1643 zeigte Torricelli, ein Schiiler Galileis, daB in der Natur ein vollig leerer Raum im aligemeinen nicht vorkommt. Der Aus druck "Torricellische Leere" fiir den Raum tiber der Queck silbersaule im Barometerrohr erinnert an ihn als den Entdecker der Tatsache, daB die Atmosphare einen Druck austibt, der dem einer Quecksilbersaule von 760 mm Hohe entspricht. Zweifellos stellte er sich gerade diesen Raum als ein "voll kommenes Vakuum" vor. Wir wissen aber heute, daB sich in dem sell>en Quecksilberdampf unter einem Druck hefindet, der ein oder mehrere Millionstel einer Atmosphare betragt; wozu noch Spuren von Wasserdampf und Luft kommen, deren Druck gleichfalls bis zu einem oder mehreren Millionstel Atmospharen betragen kann. Um 1654 erfand Otto v. Guericke die erste mechanische Luftpumpe, die spater von Boyle, Hawksbee, Smeaton u. a. verbessert worden ist. Wahrend der nachsten zweihundert Jahre hestand nur ein mehr oder weniger akademisches Interesse fiir die Vorgiinge hei geringem Druck. Die Aussichten, die Newton, Laplace und Maxwell in der mathematischen Physik und Priestley, Lavoisier und Faradayin der experimentellen Wissenschaft gezeigt hatten, waren so bestechend, daB man fiir die Untersuchung "leerer Raume" wenig oder gar kein Interesse mehr aufbrachte."

A comprehensive introduction to the structure, properties, and applications of materials

This title provides the first unified treatment for the broad subject of materials. Authors Gersten and Smith use a fundamental approach to define the structure and properties of a wide range of solids on the basis of the local chemical bonding and atomic order present in the material. Emphasizing the physical and chemical origins of material properties, the book focuses on the most technologically important materials being utilized and developed by scientists and engineers.

Appropriate for use in advanced materials courses, The Physics and Chemistry of Materials provides the background information necessary to assimilate the current academic and patent literature on materials and their applications. Problem sets, illustrations, and helpful tables complete this well-rounded new treatment.

Five sections cover these important topics:

• Structure of materials, including crystal structure, bonding in solids, diffraction and the reciprocal lattice, and order and disorder in solids
• Physical properties of materials, including electrical, thermal, optical, magnetic, and mechanical properties
• Classes of materials, including semiconductors, superconductors, magnetic materials, and optical materials in addition to metals, ceramics, polymers, dielectrics, and ferroelectrics
• A section on surfaces, thin films, interfaces, and multilayers discusses the effects of spatial discontinuities in the physical and chemical structure of materials
• A section on synthesis and processing examines the effects of synthesis on the structure and properties of various materials

This book is enhanced by a Web-based supplement that offers advanced material together with an entire electronic chapter on the characterization of materials. The Physics and Chemistry of Materials is a complete introduction to the structure and properties of materials for students and an excellent reference for scientists and engineers.

This text will thoroughly update the existing literature on atomic physics. Intended to accompany an advanced undergraduate course in atomic physics, the book will lead the students up to the latest advances and the applications to Bose-Einstein Condensation of atoms, matter-wave inter-ferometry and quantum computing with trapped ions. The elementary atomic physics covered in the early chapters should be accessible to undergraduates when they are first introduced to the subject. To complement the usual quantum mechanical treatment of atomic structure the book strongly emphasizes the experimental basis of the subject, especially in the later chapters. It includes ample tutorial material (examples, illustrations, chapter summaries, graded problem sets).

This book provides the reader with a detailed theoretical treatment of the key mechanisms of superconductivity, up to the current state of the art (phonons, magnons, plasmons). In addition, the book describes the properties of key superconducting compounds that are of most interest for science and its applications today. For many years there has been a search for new materials with higher values of the main parameters, such as the critical temperature and the critical current. At present, the possibility to observe superconductivity at room temperature has become perfectly realistic. The book is especially concerned with high Tc systems, such as the high Tc oxides, hydrides with record values of the critical temperature under high pressure, nanoclusters, etc. A number of interesting novel superconducting systems have been discovered recently. Among them: topological materials, interface systems, intercalated graphene. The book contains rigorous derivations, based on statistical mechanics and many-body theory. The book is also providing qualitative explanations of the main concepts and results, which makes it accessible and interesting for a broader readership.

Most previous texts on quantum optics have been written primarily for the graduate student market at PhD level and above. Quantum optics: an introduction aims to introduce a wide range of topics at a lower level suitable for advanced undergraduate and Masters level students in physics. The text is divided into four main parts, covering modern topics in both pure and applied quantum optics: I. Introduction and background material. II. Photons. III. Atom-photon interactions. IV. Quantum information processing. The emphasis of the subject development is on intuitive physical understanding rather than mathematical arguments, although many derivations are included where appropriate. The text includes numerous illustrations, with a particular emphasis on the experimental observations of quantum optical phenomena. Each chapter includes worked examples, together with 10-15 exercises with solutions. Six appendices are included to supplement the main subject material.

This book provides a bridge between the basic principles of physics learned as an undergraduate and the skills and knowledge required for advanced study and research in the exciting field of atomic physics. The text is organized in a unique and versatile format --- as a collection of problems, hints, detailed solutions, and in-depth tutorials. This enables the reader to open the book at any page and get a solid introduction to subjects on the cutting edge of atomic physics, such as frequency comb metrology, tests of fundamental symmetries with atoms, atomic magnetometers, atom trapping and cooling, and Bose-Einstein condensates. The text also includes problems and tutorials on important basics that every practicing atomic physicist should know, but approached from the perspective of experimentalists: formal calculations are avoided where possible in favor of 'back-of-the-envelope' estimates, symmetry arguments, and physical analogies. The 2nd edition contains over 10 new problems, and includes important updates, revisions, and corrections of several problems of the 1st edition.

This book presents a highly integrated, step-by-step approach to the design and construction of low-temperature measurement apparatus. It is effectively two books in one: A textbook on cryostat design techniques and an appendix data handbook that provides materials-property data for carrying out that design. The main text encompasses a wide range of information, written for specialists, without leaving beginning students behind. After summarizing cooling methods, Part I provides core information in an accessible style on techniques for cryostat design and fabrication - including heat-transfer design, selection of materials, construction, wiring, and thermometry, accompanied by many graphs, data, and clear examples. Part II gives a practical user's perspective of sample mounting techniques and contact technology. Part III applies the information from Parts I and II to the measurement and analysis of superconductor critical currents, including in-depth measurement techniques and the latest developments in data analysis and scaling theory. The appendix is a ready reference handbook for cryostat design, encompassing seventy tables compiled from the contributions of experts and over fifty years of literature.

Contains 106 papers from the June 1996 conference, designed as an archival reference for users and developers of cryocoolers. Papers are organized into 15 chapters by cryocooler type, starting with Stirling coolers and progressing through lower-temperature coolers including Gifford-McMahon types, lo