Download or read book Experimental Electron Density Dilute Magnetic Semiconducting Materials written by Ramachandran Saravanan and published by LAP Lambert Academic Publishing. This book was released on 2010-08 with total page 160 pages. Available in PDF, EPUB and Kindle. Book excerpt: There are many techniques that can help evolving the minute details in the spintronics materials, but X- ray diffraction technique can give fine details of these materials in the form of charge density picture and local structure. Charge density results can be analyzed qualitatively and quantitatively for the type of bonding and also for the magnetic behavior involved. Hence, a study on these materials using experimental X-ray diffraction information is inevitable for the better understanding of local structure and magnetism. This monograph deals with the technologically important diluted magnetic semiconductors (DMS), zinc oxide based diluted magnetic semiconductors and manganites (LSMO) for their local and average structures, charge density etc.

Download or read book Dilute Magnetic Semiconducting DMS Materials written by R. Saravanan and published by Materials Research Forum LLC. This book was released on 2018-08-25 with total page 203 pages. Available in PDF, EPUB and Kindle. Book excerpt: Diluted Magnetic Semiconductors (DMS) play a vital role in modern electronics industry. It is important to understand the fundamental properties of these materials in order to apply them to their full potential. This book presents an analysis of the charge density distribution and other properties of some silicon and germanium based diluted magnetic semiconductors. A quantitative analysis of the charge density distribution has been done in order to obtain measurements of the charges involved in the bonding, which are decisive for the physical and chemical properties of the DMS materials. Also, the local structures of the materials have been analyzed by studying their powder X-ray diffraction intensities. Analysis of the magnetic properties of the DMS materials is mandatory and has been accomplished by magnetic measurements carried out using a vibrating sample magnetometer. The morphology of the DMS materials has been studied using scanning electron micrographs.

Download or read book Diluted Magnetic Semiconductors written by Mukesh Kumar Jain and published by World Scientific. This book was released on 1991 with total page 682 pages. Available in PDF, EPUB and Kindle. Book excerpt: This review volume presents both basic and applied aspects of diluted magnetic semiconductors (DMS). The term DMS applies generally to semiconductors in which a fraction of its constituent ions are replaced by magnetic ions. This book is only the second to review DMS materials. It presents a detailed treatment of the current state of knowledge of the established properties of DMS in the form of single crystals, quantum wells and superlattices. It also brings together recent work on new DMS materials and presents discussions on a wide range of possible DMS applications.

Download or read book First Principle Vs Experimental Design of Diluted Magnetic Semiconductors written by Omar Mounkachi and published by Nova Science Publishers. This book was released on 2018-10 with total page 177 pages. Available in PDF, EPUB and Kindle. Book excerpt: Recent discoveries have given rise to a new class of electronics known as "spin electronics or spintronics," which uses the electron spin rather than its charge to create polarized currents. Spintronics is currently experiencing an extraordinary development with the manufacture of nanoscale devices based on ferromagnetic materials and semiconductors. Their applications are numerous, ranging from recording, electronics, and optoelectronics to quantum information. Spintronics is a new generation of electronics that has brought and continues to bring a lot of progress to information storage; this is due to the discovery of new materials with new functionalities and multiple applications. The discovery of giant magnetoresistance (GMR) in 1988 by Albert Fert and Peter Grünberg (receiver of the Nobel Prize in Physics in 2007) is considered a starting point of spintronics. GMR is based on the variation of the electric current in the presence of a magnetic field. The spintronics has made important contributions to the miniaturization desired for electronics; it uses nanometric components for processing and storing information. However, the limits of miniaturization on a nanometric scale are known, and it is imperative to develop new ways and new materials to exceed those limits. The most desired properties for these materials are high spin polarization, modular magnetic properties by an electric field and a long lifetime of the spin polarization. Among the new promising materials, we cite the following: Diluted magnetic semiconductors, which give new magnetic properties of conventional semiconductors, functional oxides (including the semi-metals and multiferroic metals) and organic semiconductors. The main theoretical challenge in this area is to understand how the macroscopic magnetic behavior observed results from interactions of a large number of degrees of microscopic freedom. In these systems the disorder is an essential parameter of magnetic phenomena, and due to random locations of impurity atoms it can lead to a total physical difference from the observed absence. There has been considerable recent advances in the design of these materials as diluted magnetic semiconductors (DMS, or diluted magnetic semiconductors), and a number of semiconductors were investigated as II-VI group and III-V group doped compounds, with transition metals substituting their original cations. There are several different theoretical approaches to study these magnetic materials. The ab-initio approach starts from the Schrödinger equation to simulate a given material. Such an approach is essential to determine the parameters and microscopic properties of such a system. In this book, the authors analyzed the electronic structure of magnetic semiconductors diluted in the case of ZnO, GaN, SnO2, TiO2, MgH2, EuO and EuN doped RENs (RE=GdN, DyN and HoN). The authors focused on magnetic, optical and exchange mechanisms which control the ferromagnetism in these systems. The purpose of this book is to propose some ideas to answer the most important question in material science for semiconductor spintronics, primarily considering how room-temperature ferromagnetism in DMS can be realized. Additionally, the correlation between first principle and experimental design to see how properties of yet-to-be-synthesized materials can be predicted is discussed.

Download or read book Introduction to the Physics of Diluted Magnetic Semiconductors written by Jan A. Gaj and published by Springer Science & Business Media. This book was released on 2011-01-12 with total page 484 pages. Available in PDF, EPUB and Kindle. Book excerpt: As materials whose semiconducting properties are influenced by magnetic ions, DMSs are central to the emerging field of spintronics. This volume focuses both on basic physical mechanisms (e.g. carrier-ion and ion-ion interactions), and resulting phenomena.

Download or read book Transition Metal Doped Spintronics Materials written by R. Saravanan and published by Materials Research Forum LLC. This book was released on 2023-02-15 with total page 116 pages. Available in PDF, EPUB and Kindle. Book excerpt: The book presents new research on the synthesis and characterization of various oxide based dilute magnetic spintronics materials (ODMS). The characterization techniques included powder X-ray diffraction, scanning electron microscopy, vibrating sample magnetometry and UV visible spectrometry. The morphological, magnetic and optical properties are reported. Electron density distribution studies are presented in the form of three, two and one dimensional electron density maps. Keywords: Spintronics Materials, Zn1-xTixO, Zn1-xFexO, Zn1-xVxO, Zn1-xNix/2Vx/2O, Synthesis, X-ray Diffraction. Rietveld Analysis, Surface Morphological Properties, Optical Properties, Magnetic Properties, Charge Density Analysis, Electron Density Distribution.

Download or read book II VI Semiconductor Materials and their Applications written by MariaC. Tamargo and published by Routledge. This book was released on 2018-05-04 with total page 382 pages. Available in PDF, EPUB and Kindle. Book excerpt: II-VI Semiconductor Materials and Their Applications deals with II-VI compound semiconductors and the status of the two areas of current optoelectronics applications: blue-green emitters and IR detectors. Specifically, the growth, charactrtization, materials and device issues for these two applications are described. Emphasis is placed on the wide bandgap emitters where much progress has occurred recently.The book also presents new directions that have potential, future applications in optoelectronics for II-VI materials. In particular, it discusses the status of dilute magnetic semiconductors for mango-optical and electromagnetic devices, nonlinear optical properties, photorefractive effects and new materials and physics phenomena, such as self-organized, low-dimensional structures.II_VI Semiconductor Materials and Their Applications is a valuable reference book for researchers in the field as well as a textbook for materials science and applied physics courses.

Download or read book Frontiers in Magnetic Materials written by A. V. Narlikar and published by Springer Science & Business Media. This book was released on 2005-04-25 with total page 832 pages. Available in PDF, EPUB and Kindle. Book excerpt: Spin Ladders and Spin Chains.- Probing Magnetic Phases in Different Systems.- Spin Glasses; From the Roots to the Present.- Magnetism in Nanostructures.- Surface and Interface Magnetism on the Atomic Scale.- Spectroscopy of Quantum Antiferromagnets.- Modern Methods for Investigating Magnetism.- Low Dimensionalmagnetism in Transition Metal Oxyborates.- Finite Temperature Half-metallic Ferromagnets.- Charge Order in Doped and Self-doped Oxides: Present Pictures.- Magnetic Tunnel Junctions Based on Half Metallic Oxides.- SrCu2 (BO3)2- a 2D Spin Gap Material.- Magnetism in Quantum Spin Systems.- Chemistry Aspects of Double Perovskites.- Magnetism in Carbon based Materials.- Microstructure Studies of Manganites by Lorentz-TEM Technique.- Local-Moment Systems: Ferromagnetism and Electronic Correlations.- Magnetism of Heavy Electron Materials.- Commenturate and Incommensurate Magnetism in Layered Antiferromagnets.- Single Crystals of Manganites and Related Materials.- Collossal Magnetoresistance and the Physics of Thin Maganite.- Dilute Magnetic Semiconductors.- Layed Co Oxides as a Thermoelectric Material.- New Magnetic Systems Exhibiting Superconductivity

Download or read book Charge Density and Structural Characterization of Thermoelectric Materials written by R. Saravanan and published by Materials Research Forum LLC. This book was released on 2016-06-01 with total page 182 pages. Available in PDF, EPUB and Kindle. Book excerpt: Thermoelectric materials permit the direct conversion of temperature differences into electric energy, and vice versa. They are therefore of highest technological interest in applications such as solid state coolers, waste heat recovery, sensors and detectors, and power generators including remote power generation. Thermoelectric materials are often called “environmentally green”, and for good reasons. Not only can they help generate electrical energy from waste gases as they are generated in such processes as home heating, industrial fabrication and automotive motion. In cooling applications they eliminate the use of chemical refrigerant gases. Moreover, as thermoelectric conversion devices have no moving parts, they operate silently and have a very long life expectancy. The only current drawback of these devices is their poor efficiency. Scientists all over the world are therefore studying the structural, thermoelectric, charge-density and magnetic properties of the most promising types of these materials at the atomic and electronic level. In addition to providing an introduction to the field, the main objective of this book is to present the results of the growth and structural characterization of thermoelectric materials that are of high current interest; including Mg2Si, PbTe, Bi1-xSbx, Bi2Te3, Sb2Te3, Sn1-xGexTe and InSb.

Download or read book Semimagnetic Semiconductors and Diluted Magnetic Semiconductors written by M. Averous and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 278 pages. Available in PDF, EPUB and Kindle. Book excerpt: Semimagnetic semiconductors (SMSC) and diluted magnetic semiconductors (DMS) have in the past decade attracted considerable attention because they confer many new physical properties on both bulk materials and heterostructures. These new effects are due either to exchange interactions between magnetic moments on magnetic ions, or to exchange interactions between magnetic moments and the spin of the charge carrier. These effects vary with the transition metal (Mn, Fe, Co) or rare earth (Eu, Gd, etc) used and thus provide a range of different situations. The field is very large (zero gap, small gap, wide gap), and the magnetic properties also are very rich (paramagnetic spin glass, antiferromagnetism). These materials are very convenient for studying the magnetism (the magnetism is diluted) or the superlattices (SL) with a continuous change from type II SL to type III SL. This Course attempted to provide a complete overview of the topic. The participants of this summer school held in Erice came from ten countries and were from various backgrounds and included theoreticians, experimentalists, physicists, and chemists. Consequently, an attempt was made to make the Course as thorough as possible, but at the same time attention was devoted to basic principles. The lecturers, drawn from all the groups in the world involved in the field, were asked to be very didactic in their presentation. After two introductory lectures, Dr.

Download or read book Investigaton of the Suitability of Wide Bandgap Dilute Magnetic Semiconductors for Spintronics written by Matthew Hartmann Kane and published by . This book was released on 2007 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: New semiconductor materials may enable next-generation 'spintronic' devices which exploit both the spin and charge of an electron for data processing, storage, and transfer. The realization of such devices would benefit greatly from room temperature ferromagnetic dilute magnetic semiconductors. Theoretical predictions have suggested that room temperature ferromagnetism may be possible in the wide bandgap semiconductors GaMnN and ZnMnO, though the existing models require input from the growth of high-quality materials. This work focuses on an experimental effort to develop high-quality materials in both of these wide bandgap materials systems. ZnMnO and ZnCoO single crystals have been grown by a modified melt growth technique. X-ray diffraction was used to examine the structural quality and demonstrate the single crystal character of these devices. Substitutional transition metal incorporation has been verified by optical transmission and electron paramagnetic resonance measurements. No indications of ferromagnetic hysteresis are observed from the bulk single crystal samples, and temperature dependent magnetization studies demonstrate a dominant antiferromagnetic exchange interaction. Efforts to introduce ferromagnetic ordering were only successful through processing techniques which significantly degraded the material quality. GaMnN thin films were grown by metalorganic chemical vapor deposition. Good crystalline quality and a consistent growth mode with Mn incorporation were verified by several independent characterization techniques. Substitutional incorporation of Mn on the Ga lattice site was confirmed by electron paramagnetic resonance. Mn acted as a deep acceptor in GaN. Nevertheless, ferromagnetic hysteresis was observed in the GaMnN films. The apparent strength of the magnetization correlated with the relative ratio of trivalent to divalent Mn. Valence state control through codoping with additional donors such as silicon was observed. Additional studies on GaFeN also showed a magnetic hysteresis. A comparison with implanted samples showed that the common origin to the apparent strong ferromagnetic hysteresis related to contribution from Mn substitutional ions. The observed magnetic hysteresis is due to the formation of Mn-rich regions during the growth process. This work demonstrated that the original intrinsic models for room temperature ferromagnetism in the wide bandgap semiconductors do not hold and the room temperature ferromagnetism in these materials results from extrinsic contributions.

Download or read book Electron and Magnetization Densities in Molecules and Crystals written by Pierre Becker and published by Springer Science & Business Media. This book was released on 2013-11-21 with total page 885 pages. Available in PDF, EPUB and Kindle. Book excerpt: The interest of describing the ground state properties of a system in terms of one electron density (or its two spin components) is obvious, in particular due to the simple physical significance of this function. Recent experimental progress in diffraction made the measurement of charge and magnetization densities in crystalline solids possible, with an accuracy at least as good as theoretical accuracy. Theoretical developments of the many-body problem have proved the extreme importance of the one electron density function and presently, accurate methods of band structure determination become available. Parallel to the diffraction techniques, other domains of research (inelastic scattering, resonance, molecular spectroscopy) deal with quantities directly related to the one particle density. But the two types of studies do not interfere enough and one should obviously gain more information by interpreting all experiments that are related to the density together. It became necessary to have an International School that reviews the status of the art in the domain of "ELECTRON AND MAGNETIZATION DENSITIES IN MOLECULES AND CRYSTALS". This was made possible through the generous effort of N.A.T.O. 's Scientific Affairs Division, and I would specially thank Dr. T. KESTER, the head of this Division, for his help and competence. An Advanced Study Institute was thus held in ARLES, south France, from the 16th to the 31st of August 1978.

Download or read book Handbook of Spintronic Semiconductors written by Weimin Chen and published by CRC Press. This book was released on 2019-05-08 with total page 348 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book provides an in-depth review of the rapidly developing field of spintronic semiconductors. It covers a broad range of topics, including growth and basic physical properties of diluted magnetic semiconductors based on II-VI, III-V and IV semiconductors, recent developments in theory and experimental techniques and potential device applications; its aim is to provide postgraduate students, researchers and engineers a comprehensive overview of our present knowledge and future perspectives of spintronic semiconductors.

Download or read book Spintronics Handbook Second Edition Spin Transport and Magnetism written by Evgeny Y. Tsymbal and published by CRC Press. This book was released on 2019-05-20 with total page 497 pages. Available in PDF, EPUB and Kindle. Book excerpt: The second edition offers an update on the single most comprehensive survey of the two intertwined fields of spintronics and magnetism, covering the diverse array of materials and structures, including silicon, organic semiconductors, carbon nanotubes, graphene, and engineered nanostructures. It focuses on seminal pioneering work, together with the latest in cutting-edge advances, notably extended discussion of two-dimensional materials beyond graphene, topological insulators, skyrmions, and molecular spintronics. The main sections cover physical phenomena, spin-dependent tunneling, control of spin and magnetism in semiconductors, and spin-based applications.

Download or read book Advanced Functional Materials written by and published by Newnes. This book was released on 2012-12-31 with total page 258 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book deals with functional materials that are in the frontiers of current materials science and technology research, development and manufacture. The first of its kind, it deals with three classes of materials, (1) magnetic semiconductors, (2) multiferroics, and (3) graphene. Because of the wide popularity of these materials there is a strong need for a book about these materials for graduate students, new researchers in science and technology, as well as experienced scientists and technologists, technology based companies and government institutes for science and technology. The book will provide this broad audience with both theoretical and experimental understanding to help in technological advances in the development of devices and related new technologies based on these very interesting and novel materials. - Covers both the theoretical and experimental aspects of advanced functional materials, which are important for use in a number of rapidly developing novel technological devices - Includes excellent coverage of three of the leading advanced functional materials - Edited by a leading expert at the forefront of advanced functional materials research

Download or read book Ferrite Materials for Memory Applications written by R. Saravanan and published by Materials Research Forum LLC. This book was released on 2017-11-10 with total page 172 pages. Available in PDF, EPUB and Kindle. Book excerpt: In the modern world, the life style of humans is greatly influenced by electronic gadgets. These electronic gadgets need semiconducting and magnetic materials. In particular, the magnetic materials which find applications in almost all such gadgets need to be researched and better understood. Magnetism has diverse applications, from simple “loadstone” to complex DNA sequencing. The aim of this book is to describe the synthesis and characterization of various nano ferrite materials used for memory applications. It is now well established that materials synthesized in nanometer scale have novel properties compared to their bulk counterparts. The distinct feature of the book is the construction of charge density diagrams of ferrites by using the maximum entropy method (MEM). It is analyzed how the charge density distribution in the ferrite unit cell affects charge related properties. Magnetic Materials, Nano Ferrite Materials Characterization Techniques, Dielectric Studies, Maximum Entropy Method (MEM), Magnetic Properties, Optical Properties, Dielectric Properties

Download or read book Titanate Based Ceramic Dielectric Materials written by R. Saravanan and published by Materials Research Forum LLC. This book was released on 2018-02-25 with total page 167 pages. Available in PDF, EPUB and Kindle. Book excerpt: Barium titanate is one of the most important electronic materials; due to its high permittivity, low dielectric loss and high tunability. The environment friendly material is suitable for microphones and microwave device applications such as tunable capacitors, delay lines, filters, resonators and phase shifters. Doped titanates are extensively used for various electronic devices, such as transducers, piezoelectric actuators, passive memory storage devices, dynamic random access memory (DRAM), multilayer ceramic capacitors (MLCCs), positive temperature coefficient resistors (PTCR), optoelectronic devices and infrared sensors. The book presents research results concerning the electron density distribution in a number of doped barium titanate ceramic materials using experimental X-ray diffraction data, UV-visible spectrophotometry (UV-vis), scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS). The analysis of interatomic bonding and electron density distribution is important for predicting the properties of potentially important materials and has previously been lacking for the materials studied. Barium Titanate, Barium Titanate Doping, Dielectric Ceramics, Permittivity, Tunability, Transducers, Piezoelectric Actuators, Memory Storage Devices, Multilayer Ceramic Capacitors, Optoelectronic Devices, X-Ray Diffraction Data, UV-Visible Spectrophotometry, Energy Dispersive X-Ray Spectroscopy, Interatomic Bonding, Electron Density Distribution, Ceramic Property Predictions.