This book begins by introducing magnetism and discusses magnetic properties of materials, magnetic moments of atoms and ions, and the elements important to magnetism. It covers magnetic susceptibilities and electromagnetic waves in anisotropic dispersive media among other topics. There are problems at the end of each chapter, many of which serve to expand or explain the material in the text. The bibliographies for each chapter give an entry to the research literature.
This book presents recent scientific achievements in the investigation of magnetization dynamics in confined magnetic systems. The book will be of value for scientists and engineers working on magnetic storage elements and magnetic logic, and is also suitable as an advanced textbook for graduate students.
This book presents a collection of problems in spin wave excitations with their detailed solutions. Each chapter briefly introduces the important concepts, encouraging the reader to further explore the physics of spin wave excitations and the engineering of spin wave devices by working through the accompanying problem sets. The initial chapters cover the fundamental aspects of magnetization, with its origins in quantum mechanics, followed by chapters on spin wave excitations, such as the magnetostatic approximation, Walker's equation, the spin wave manifold in the three different excitation geometries of forward volume, backward volume and surface waves, and the dispersion of spin waves. The latter chapters focus on the practical aspects of spin waves and spin wave optical devices and use the problem sets to introduce concepts such as variational analysis and coupled mode theory. Finally, for the more advanced reader, the book covers nonlinear interactions and topics such as spin wave quantization, spin torque excitations, and the inverse Doppler effect. The topics range in difficulty from elementary to advanced. All problems are solved in detail and the reader is encouraged to develop an understanding of spin wave excitations and spin wave devices while also strengthening their mathematical, analytical, and numerical programming skills.
In the past few years, there has been a rapidly growing interest in the properties of spin waves (or magnons) in ordered magnetic materials. These are the low-lying excitations that characterize the dynamical behavior of the magnetization variables in ferromagnets, ferrimagnets and antiferromagnets, particularly at low temperatures. Many of the recent developments concerning spin waves have been directed towards understanding their behavior in limited magnetic samples. At the same time, there have been dramatic advances in the experimental techniques, both for preparing high-quality magnetic samples in the form of thin films and superlattices and for the study of the spin-wave excitations themselves. Magnetic thin films have long been of technological as well as scientific interest and an understanding of both the linear and nonlinear aspects of their magnetic behavior is important.
Modern Problems in Condensed Matter Sciences, Volume 22.1: Spin Waves and Magnetic Excitations, Part I focuses on the principles, methodologies, approaches, and reactions involved in spin waves and magnetic excitations, including, Brillouin-Mandelstam light scattering, optical magnetic excitations, and magnetic dielectrics. The selection first elaborates on spin waves in magnetic dielectrics current status of the theory and light scattering from spin waves. Discussions focus on magneto-optic effects and the mechanism of light scattering in magnets, Brillouin-Mandelstam light scattering, Raman scattering, Collinear Heisenberg ferromagnet, low-temperature phase transitions, and low-dimensional systems. The text then ponders on optical magnetic excitations, spin waves above the threshold of parametric excitations, and theory of spin excitations in rare earth systems. Topics include Hamiltonian for rare earth systems, parametric instability of spin waves in magnetic dielectrics, nonstationary processes in parametric excitation of spin waves, radiative decay of magnetic excitons, and mechanism of the generation of magnetic excitations by light. The book tackles 4f moments and their interaction with conduction electrons and neutron scattering studies of magnetic excitations in itinerant magnets, including magnetic excitations at finite and low temperatures, paramagnetic scattering, coupling to conduction electrons, and virtual magnetic excitations. The selection is highly recommended for researchers wanting to study spin waves and magnetic excitations.
The aim of this advanced textbook is to provide the reader with a comprehensive explanation of the ground state configurations, the spin wave excitations and the equilibrium properties of spin lattices described by the IsingOCoHeisenberg Hamiltonians in the presence of short (exchange) and long range (dipole) interactions.The arguments are presented in such detail so as to enable advanced undergraduate and graduate students to cross the threshold of active research in magnetism by using both analytic calculations and Monte Carlo simulations.Recent results about unorthodox spin configurations such as stripes and checkerboards should then excite theoreticians in the field of magnetism and magnetic materials research.
In the past few years, there has been a rapidly growing interest in the properties of spin waves (or magnons) in ordered magnetic materials. These are the low-lying excitations that characterize the dynamical behavior of the magnetization variables in ferromagnets, ferrimagnets and antiferromagnets, particularly at low temperatures. Many of the recent developments concerning spin waves have been directed towards understanding their behavior in limited magnetic samples. At the same time, there have been dramatic advances in the experimental techniques, both for preparing high-quality magnetic samples in the form of thin films and superlattices and for the study of the spin-wave excitations themselves. Magnetic thin films have long been of technological as well as scientific interest and an understanding of both the linear and nonlinear aspects of their magnetic behavior is important.
This is a book of informal research papers written by George J Bugh while investigating claims by many inventors and researchers who have built unusual electromagnetic devices said to produce anomalous energy output and even electrogravity effects.Mr. Bugh is a senior staff aerospace electronics engineer with over 20 years experience. He spent the last 7 years studying these claims to determine if any could be valid and if so then to determine the source of the anomalous energy and the electrogravity effects.According to classical electrodynamics, all electrically charged particles, like quarks and electrons, should radiate away energy from gyroscopic precessional motions and orbital motions. Bugh has come to the conclusion that they really do. However, all particles are also absorbing just as much energy from all other radiating particles.The continuously absorbed energy equals the radiated energy and applies forces that move similar type particles into harmonious precesssional motions with each other. This results in a sea of electromagnetic standing waves among all matter in the universe.It is this sea of standing waves rather than quantum probability waves that best account for the wave like nature of matter. Particles move to quantized states because of electromagnetic forces that keep particle motions synchronized with this sea of standing waves.This is an interaction among all matter that Ernst Mach alluded to as necessary to cause matter's characteristic of inertia. Einstein called this Mach's Principle. Einstein studied Mach's ideas while developing his theory of General Relativity.Using common sense and classical electrodynamics, Bugh explains how these particle spin interactions are possible even among compensating spins. Technology advancements are possible based on these particle spin interactions.
Written by two well-known researchers in the field, this useful reference takes an applied approach to high frequency processes including oscillations and waves in ferromagnets, antiferromagnets, and ferrimagnets. Problems evaluated include ferromagnetic and antiferromagnetic resonances, spin waves, nonlinear processes, and high frequency manifestations of interactions between the magnetic system and other systems of magnetically ordered substances as elastic waves and charge carriers. Unlike previous monographs on this subject, which are highly theoretical and written for very advanced readers, this book requires only an average college background in mathematics and experimental physics. It will be a valuable addition to the library of engineers and scientists in research and development for communications applications, and scientists interested in nonlinear magnetic phenomena. It also serves as an excellent introduction to the topic for newcomers in the field. Magnetization Oscillations and Waves not only presents results but also shows readers how to obtain them; most formulas are derived with so many details that readers can reproduce them. The book includes many summaries and tables and detailed references to significant work in the area by European researchers.
