Growth And Characterization Of Bulk Superconductor Material

Author: Dapeng Chen
Publisher: Springer
ISBN: 331931548X
Size: 17.34 MB
Format: PDF, Docs
View: 2990
Download
This book focuses on recently developed crystal growth techniques to grow large and high quality superconducting single crystals. The techniques applied are traveling solvent floating zone (TSFZ) with infrared image furnace, Bridgeman, solution/flux and top seeded solution growth (TSSG) methods. The materials range from cuprates, cobaltates to pnictides including La2CuO4-based (LCO), YBa2Cu3O7-d (YBCO), Bi2Sr2Can−1CunO2n+4+δ (n=1,2,3) (BSCCO) to NaxCoO2. The modified Bridgman “cold finger” method is devoted to the pnictide system with the best quality (transition width DTc~0.5 K) with highest Tc~38.5 K of Ba0.68K0.32Fe2A2. The book presents various iron-based superconductors with different structures, such as 1111, 122, 111, 11 and 42622,10-3-8. Detailed single crystal growth methods (fluxes, Bridgman, floating zone), the associated procedures and their impact to crystal size and quality are presented. The book also describes the influence of doping on the structure and the electric, magnetic, and superconducting properties of these compounds in a comparative study of different growth methods. It describes particularly under-, optimal and over-doped with oxygen cuprates (LCO, YBCO and BSCCO) and hole/electron/isovalently doped parent compounds AFe2As2 (A = Ba, Sr, Ca) (122), chalcogenides AxFe2-ySe2(A = K, Rb, Cs) (122), and Fe1-dTe1-xSex (11). A review of the current growth technologies and future growth efforts handling volatile and poisonous components are also presented.

Iron Based Superconductivity

Author: Peter D. Johnson
Publisher: Springer
ISBN: 3319112546
Size: 11.84 MB
Format: PDF, Mobi
View: 1902
Download
This volume presents an in-depth review of experimental and theoretical studies on the newly discovered Fe-based superconductors. Following the Introduction, which places iron-based superconductors in the context of other unconventional superconductors, the book is divided into three sections covering sample growth, experimental characterization, and theoretical understanding. To understand the complex structure-property relationships of these materials, results from a wide range of experimental techniques and theoretical approaches are described that probe the electronic and magnetic properties and offer insight into either itinerant or localized electronic states. The extensive reference lists provide a bridge to further reading. Iron-Based Superconductivity is essential reading for advanced undergraduate and graduate students as well as researchers active in the fields of condensed matter physics and materials science in general, particularly those with an interest in correlated metals, frustrated spin systems, superconductivity, and competing orders.

Flux Pinning In Superconductors

Author: Teruo Matsushita
Publisher: Springer Science & Business Media
ISBN: 3642453120
Size: 38.13 MB
Format: PDF, ePub, Mobi
View: 6209
Download
The book covers the flux pinning mechanisms and properties and the electromagnetic phenomena caused by the flux pinning common for metallic, high-Tc and MgB2 superconductors. The condensation energy interaction known for normal precipitates or grain boundaries and the kinetic energy interaction proposed for artificial Nb pins in Nb-Ti, etc. are introduced for the pinning mechanism. Summation theories to derive the critical current density are discussed in detail. Irreversible magnetization and AC loss caused by the flux pinning are also discussed. The loss originally stems from the ohmic dissipation of normal electrons in the normal core driven by the electric field induced by the flux motion. The readers will learn why the resultant loss is of hysteresis type in spite of such mechanism. The influence of the flux pinning on the vortex phase diagram in high Tc superconductors is discussed and the dependencies of the irreversibility field are also described on other quantities such as anisotropy of superconductor, specimen size and electric field strength. Recent developments of critical current properties in various high-Tc superconductors and MgB2 are introduced. Other topics are: singularity in the case of transport current in a parallel magnetic field such as deviation from the Josephson relation, reversible flux motion inside pinning potentials which causes deviation from the critical state model prediction, the concept of the minimization of energy dissipation in the flux pinning phenomena which gives the basis for the critical state model, etc. Significant reduction in the AC loss in AC wires with very fine filaments originates from the reversible flux motion which is dominant in the two-dimensional pinning. The concept of minimum energy dissipation explains also the behavior of flux bundle size which determines the irreversibility line under the flux creep. The new edition has been thoroughly updated, with new sections on the progress in enhancing the critical current density in high temperature superconductors by introduction of artificial pinning centers, the effect of packing density on the critical current density and irreversibility field in MgB2 and derivation of the force-balance equation from the minimization of the free energy including the pinning energy.

Unconventional Superconductors

Author: Iman Askerzade
Publisher: Springer Science & Business Media
ISBN: 3642226523
Size: 76.36 MB
Format: PDF, Docs
View: 3428
Download
This book presents the anisotropy and multiband effects in newly discovered unconventional superconductors: cuprate superconductors, borocarbides, magnezium-diboride and oxypnictides. The physical properties of these unconventional superconductors and the application of the two-band Ginzburg-Landau theory to these superconducting compounds are explained. Temperature dependencies of fundamental superconducting parameters are calculated using the GL theory taking into account multiband-and anisotropy effects. A comparision of theoretical results and experimental data is conducted. Additionally, the analytical solution of the microscopical Eliashberg theory and of the BCS theory is developed for two-band and anisotropic superconductors. Fluctuation effects in newly discovered superconductors are also discussed.

Physics And Engineering Of New Materials

Author: Do Tran Cat
Publisher: Springer Science & Business Media
ISBN: 3540882014
Size: 35.48 MB
Format: PDF, ePub, Docs
View: 2365
Download
This book presents the majority of the contributions to the Tenth German-Vietnamese Seminar on Physics and Engineering (GVS10) that took place in the Gustav- Stresemann-Institut (GSI) in Bonn from June 6 to June 9, 2007. In the focus of these studies are the preparation and basic properties of new material systems, related investigation methods, and practical applications. Accordingly the sections in this book are entitled electrons: transport and confinement, low-dimensional systems, magnetism, oxidic materials, organic films, new materials, and methods. The series of German-Vietnamese seminars was initiated and sponsored by the Gottlieb Daimler- and Karl Benz -Foundation since 1998 and took place alt- nately in both countries. These bilateral meetings brought together top-notch senior and junior Vietnamese scientists with German Scientists and stimulated many contacts and co-operations. Under the general title “Physics and Engine- ing” the programs covered, in the form of keynote-lectures, oral presentations and posters, experimental and theoretical cutting-edge material-physics oriented topics. The majority of the contributions was dealing with modern topics of material science, particularly nanoscience, which is a research field of high importance also in Vietnam. Modern material science allows a quick transfer of research results to technical applications, which is very useful for fast developing countries like Vietnam. On the other hand, the seminars took profit from the strong cro- fertilization of the different disciplines of physics. This book is dedicated to the tenth anniversary of the seminars and nicely shows the scientific progress in Vietnam and the competitive level reached.

Semiconductor Materials For Solar Photovoltaic Cells

Author: M. Parans Paranthaman
Publisher: Springer
ISBN: 3319203312
Size: 48.40 MB
Format: PDF, ePub
View: 4197
Download
This book reviews the current status of semiconductor materials for conversion of sunlight to electricity, and highlights advances in both basic science and manufacturing. Photovoltaic (PV) solar electric technology will be a significant contributor to world energy supplies when reliable, efficient PV power products are manufactured in large volumes at low cost. Expert chapters cover the full range of semiconductor materials for solar-to-electricity conversion, from crystalline silicon and amorphous silicon to cadmium telluride, copper indium gallium sulfide selenides, dye sensitized solar cells, organic solar cells, and environmentally friendly copper zinc tin sulfide selenides. The latest methods for synthesis and characterization of solar cell materials are described, together with techniques for measuring solar cell efficiency. Semiconductor Materials for Solar Photovoltaic Cells presents the current state of the art as well as key details about future strategies to increase the efficiency and reduce costs, with particular focus on how to reduce the gap between laboratory scale efficiency and commercial module efficiency. This book will aid materials scientists and engineers in identifying research priorities to fulfill energy needs, and will also enable researchers to understand novel semiconductor materials that are emerging in the solar market. This integrated approach also gives science and engineering students a sense of the excitement and relevance of materials science in the development of novel semiconductor materials. · Provides a comprehensive introduction to solar PV cell materials · Reviews current and future status of solar cells with respect to cost and efficiency · Covers the full range of solar cell materials, from silicon and thin films to dye sensitized and organic solar cells · Offers an in-depth account of the semiconductor material strategies and directions for further research · Features detailed tables on the world leaders in efficiency demonstrations · Edited by scientists with experience in both research and industry

Anomalous X Ray Scattering For Materials Characterization

Author: Yoshio Waseda
Publisher: Springer
ISBN: 354046008X
Size: 33.14 MB
Format: PDF
View: 2114
Download
The production of multi layered thin films with sufficient reliability is a key technology for device fabrication in micro electronics. In the Co/Cu type multi layers, for example, magnetoresistance has been found as large as 80 % at 4. 2 K and 50 % at room temperature. In addition to such gigantic mag netoresistance, these multi layers indicate anti ferromagnetic and ferromag netic oscillation behavior with an increase in the thickness of the layers of the non magnetic component. These interesting properties of the new synthetic flmctional materials are attributed to their periodic and interracial structures at a microscopic level, although the origin of such peculiar features is not fully understood. Information on the surface structure or the number density of atoms in the near surface region may provide better insight. Amorphous alloys, frequently referred to as metallic glasses, are produced by rapid quenching from the melt. The second generation amorphous alloys, called "bulk amorphous alloys", have been discovered in some Pd based and Zr based alloy systems, with a super cooled liquid region at more than 120 K. In these alloy systems, one can obtain a sample thickness of several centime ters. Growing scientific and technological curiosity about the new amorphous alloys has focused on the fundamental factors, such as the atomic scale struc ture, which are responsible for the thermal stability with certain chemical compositions.

Physical Foundations Of Materials Science

Author: Günter Gottstein
Publisher: Springer Science & Business Media
ISBN: 3662092913
Size: 66.85 MB
Format: PDF
View: 6671
Download
In this vivid and comprehensible introduction to materials science, the author expands the modern concepts of metal physics to formulate basic theory applicable to other engineering materials, such as ceramics and polymers. Written for engineering students and working engineers with little previous knowledge of solid-state physics, this textbook enables the reader to study more specialized and fundamental literature of materials science. Dozens of illustrative photographs, many of them transmission electron microscopy images, plus line drawings, aid developing a firm appreciation of this complex topic. Hard-to-grasp terms such as "textures" are lucidly explained - not only the phenomenon itself, but also its consequences for the material properties. This excellent book makes materials science more transparent.

Electron Backscatter Diffraction In Materials Science

Author: Adam J. Schwartz
Publisher: Springer Science & Business Media
ISBN: 9780306464874
Size: 29.73 MB
Format: PDF, ePub, Mobi
View: 5259
Download
Crystallographic texture or preferred orientation has long been known to strongly influence material properties. Historically, the means of obtaining such texture data has been though the use of x-ray or neutron diffraction for bulk texture measurements, or transmission electron microscopy or electron channeling for local crystallographic information. In recent years, we have seen the emergence of a new characterization technique for probing the microtexture of materials. This advance has come about primarily through the automated indexing of electron backscatter diffraction (EBSD) patterns. The first commercially available system was introduced in 1994, and since then of sales worldwide has been dramatic. This has accompanied widening the growth applicability in materials scienceproblems such as microtexture, phase identification, grain boundary character distribution, deformation microstructures, etc. and is evidence that this technique can, in some cases, replace more time-consuming transmission electron microscope (TEM) or x-ray diffraction investigations. The benefits lie in the fact that the spatial resolution on new field emission scanning electron microscopes (SEM) can approach 50 nm, but spatial extent can be as large a centimeter or greater with a computer controlled stage and montagingofthe images. Additional benefits include the relative ease and low costofattaching EBSD hardware to new or existing SEMs. Electron backscatter diffraction is also known as backscatter Kikuchi diffraction (BKD), or electron backscatter pattern technique (EBSP). Commercial names for the automation include Orientation Imaging Microscopy (OIMTM) and Automated Crystal Orientation Mapping (ACOM).

Biomimetics In Materials Science

Author: Michael Nosonovsky
Publisher: Springer Science & Business Media
ISBN: 1461409268
Size: 29.67 MB
Format: PDF, Docs
View: 7538
Download
Biomimetics in Materials Science provides a comprehensive theoretical and practical review of biomimetic materials with self-healing, self-lubricating and self-cleaning properties. These three topics are closely related and constitute rapidly developing areas of study. The field of self-healing materials requires a new conceptual understanding of this biomimetic technology, which is in contrast to traditional engineering processes such as wear and fatigue. Biomimetics in Materials Science is the first monograph to be devoted to these materials. A new theoretical framework for these processes is presented based on the concept of multi-scale structure of entropy and non-equilibrium thermodynamics, together with a detailed review of the available technology. The latter includes experimental, modeling, and simulation results obtained on self-healing/lubricating/cleaning materials since their emergence in the past decade.