Download or read book Ferromagnetic Cluster Spin Wave Theory written by Krunoslav Prsa and published by . This book was released on 2018 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Spin Waves written by Daniel D. Stancil and published by Springer Science & Business Media. This book was released on 2009-04-05 with total page 348 pages. Available in PDF, EPUB and Kindle. Book excerpt: 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.
Download or read book Spin Waves and Magnetic Excitations written by and published by Elsevier. This book was released on 2012-12-02 with total page 512 pages. Available in PDF, EPUB and Kindle. Book excerpt: Modern Problems in Condensed Matter Sciences, Volume 22.2: Spin Waves and Magnetic Excitations focuses on the processes, methodologies, reactions, principles, and approaches involved in spin waves and magnetic excitations, including magnetic systems, fluctuations, resonance, and spin dynamics. The selection first elaborates on spin-wave resonance in metals, excitations in low-dimensional magnetic systems, and the theory of magnetic excitations in disordered systems. Topics include spin waves in ferromagnets with weak fluctuations of the exchange interaction; dynamics of propagating excitations; models of two-dimensional magnetic systems; spin-wave resonance in bulk metals; and standing spin-wave resonance in thin films. The manuscript then ponders on spin dynamics of amorphous magnets and magnetic excitations in spin glasses, including dynamics in reentrant spin glasses, dynamics of classical spin glasses, spin dynamical theory, spin dynamics of locally isotropic materials, and effects of dilution. The book takes a look at nuclear spin and magnetoelastic excitations and magnetic impuritons in antiferromagnetic dielectric crystals. Discussions focus on coherent and incoherent impurity excitations, equations of motion and the energy of a magnetoelastic medium, magnetoelastic excitations near magnetic orientational phase transitions, and the effect of frequency pulling on the behavior of nuclear spin echo signals. The selection is a vital source of data for researchers interested in spin waves and magnetic excitations.
Download or read book Spin Wave Confinement written by Sergej O. Demokritov and published by CRC Press. This book was released on 2019-05-08 with total page 240 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents recent scientific achievements in the investigation of magnetization dynamics in confined magnetic systems. Introduced by Bloch as plane waves of magnetization in unconfined ferromagnets, spin waves currently play an important role for description of very small systems.Spin wave confinement effect was experimentally discovered in the 1990s in permalloy microstripes. The diversity of systems where this effect is observed has been steadily growing since then, most of which will be addressed in this book. The book includes six chapters which originate from different groups of experimentalists and theoreticians dominating the field since the discovery of the effect. Different chapters of the book reflect different facets of spin wave confinement, providing a comprehensive description of the effect and its place in modern magnetism. It 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.
Download or read book Magnetic Systems with Competing Interactions written by H. T. Diep and published by World Scientific. This book was released on 1994 with total page 351 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is intended for postgraduate students as well as researchers in various areas of physics such as statistical physics, magnetism and materials sciences. The content of the book covers mainly frustrated spin systems with possible applications in domains where physical systems can be mapped into the spin language. Pedagogical effort has been made to make each chapter to be self-contained, comprehensible for researchers who are not really involved in the field. Basic methods are given in detail.
Download or read book An Introduction to Quantum Spin Systems written by John B. Parkinson and published by Springer. This book was released on 2010-08-26 with total page 159 pages. Available in PDF, EPUB and Kindle. Book excerpt: The topic of lattice quantum spin systems is a fascinating and by now well established branch of theoretical physics. Based on a set of lectures, this book has a level of detail missing from others, and guides the reader through the fundamentals of the field.
Download or read book Spin wave Theory and Its Applications to Neutron Scattering and THz Spectroscopy written by Randy S. Fishman and published by . This book was released on 2018 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Two of the most powerful tools used to study magnetic materials are inelastic neutron scattering and THz spectroscopy. Because the measured spectra provide a dynamical fingerprint of a magnetic material, those tools enable scientists to unravel the structure of complex magnetic states and to determine the microscopic interactions that produce them. This book discusses the experimental techniques of inelastic neutron scattering and THz spectroscopy and provides the theoretical tools required to analyze their measurements using spin-wave theory. For most materials, this analysis can resolve the microscopic magnetic interactions such as exchange, anisotropy, and Dzyalloshinskii-Moriya interactions. Assuming a background in elementary statistical mechanics and a familiarity with the quantized harmonic oscillator, this book presents a comprehensive review of spin-wave theory and its applications to both inelastic neutron scattering and THz spectroscopy. Spin-wave theory is used to study several model magnetic systems, including non-collinear magnets such as spirals and cycloids that are produced by geometric frustration, competing exchange interactions, or Dzyalloshinskii-Moirya interactions. Several case studies utilizing spin-wave theory to analyze inelastic neutron-scattering and THz spectroscopy measurements are presented. These include both single crystals and powders and both oxides and molecule-based magnets. In addition to sketching the numerical techniques used to fit dynamical spectra based on microscopic models, this book also contains over 70 exercises that can be performed by beginning graduate students.
Download or read book Propagation and Interference of Spin Waves in Ferromagnetic Thin Films written by Korbinian Perzlmaier and published by . This book was released on 2008 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis deals with the propagation of spin waves in thin Ni80Fe20 films. Its specific aims are to experimentally determine a dispersion relation for propagating spin waves in thin ferromagnetic films, and to determine phase velocities, group velocities and damping. Additonally, an analytic dispersion relation based upon the linearized Landau-Lifshitz-Gilbert (LLG) equation is derived, from which the experimental findings can be reproduced using a theoretical model. Further on, this thesis reports on the direct observation of the interference of spin waves. This thesis is structured as follows: After an introduction in chapter 1, the basic principles of magnetostatics are sketched in chapter 2, followed by the principles of magnetodynamics in chapter 3. Based upon these principles, in chapter 4 a theory for the propagation of spin waves in ferromagnetic thin films is developed. The experimental part of this thesis begins with an overview of the experimental setup for Time Resolved Scanning Kerr Microscopy (TRSKEM) in chapter 5, and continues with the results of spin wave propagation and interference in chapter 6. The experimental results are compared to the theoretical predictions of the model developed in chapter 4. Chapter 7 gives a summary of the results and an outlook towards possible future developments. The appendix gives additional information on experimental and theoretical details.
Download or read book Theory of Spin Wave Excitations in Ferromagnetic Films written by R. C. Moul and published by . This book was released on 1981 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Renormalization Group Theory written by Ulrich Köbler and published by Springer Science & Business Media. This book was released on 2010-04-29 with total page 402 pages. Available in PDF, EPUB and Kindle. Book excerpt: Spin wave theory of magnetism and BCS theory of superconductivity are typical theories of the time before renormalization group (RG) theory. The two theories consider atomistic interactions only and ignore the energy degrees of freedom of the continuous (infinite) solid. Since the pioneering work of Kenneth G. Wilson (Nobel Prize of physics in 1982) we know that the continuous solid is characterized by a particular symmetry: invariance with respect to transformations of the length scale. Associated with this symmetry are particular field particles with characteristic excitation spectra. In diamagnetic solids these are the well known Debye bosons. This book reviews experimental work on solid state physics of the last five decades and shows in a phenomenological way that the dynamics of ordered magnets and conventional superconductors is controlled by the field particles of the infinite solid and not by magnons and Cooper pairs, respectively. In the case of ordered magnets the relevant field particles are called GSW bosons after Goldstone, Salam and Weinberg and in the case of superconductors the relevant field particles are called SC bosons. One can imagine these bosons as magnetic density waves or charge density waves, respectively. Crossover from atomistic exchange interactions to the excitations of the infinite solid occurs because the GSW bosons have generally lower excitation energies than the atomistic magnons. According to the principle of relevance the dynamics is governed by the excitations with the lowest energy. The non relevant atomistic interactions with higher energy are practically unimportant for the dynamics.
Download or read book Microscopic Theory of Spin Wave Dynamics in Ferromagnetic Films written by Dimosthenis Kontos and published by . This book was released on 1983 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Theory of Spin Wave Interactions in Ferromagnetism written by MARYLAND UNIV COLLEGE PARK. and published by . This book was released on 1961 with total page 1 pages. Available in PDF, EPUB and Kindle. Book excerpt: The interactions of spin waves in an ideal Heisenberg model of a ferromagnet are studied. In particular, the effect of spin wave interactions on the free energy and spontaneous magnetization are examined. Treating a spin wave as a local phenomena, only binary collisions between spin waves need be considered at low temperature. The free energy of the system is developed as an expansion in terms of a binary kernal function; this binary kernal function is determined from the two particle propagator, which can formally be evaluated. When the free energy expansion is evaluated, the results of Dyson are obtained. That is, the lowest order correction term introduced in the spontaneous magnetization by spin wave interactions is of order T(4). (Author).
Download or read book Frustrated Spin Systems written by H. T. Diep and published by World Scientific. This book was released on 2013 with total page 644 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book covers all principal aspects of currently investigated frustrated systems, from exactly solved frustrated models to real experimental frustrated systems, going through renormalization group treatment, Monte Carlo investigation of frustrated classical Ising and vector spin models, low-dimensional systems, spin ice and quantum spin glass. The reader can OCo within a single book OCo obtain a global view of the current research development in the field of frustrated systems.This new edition is updated with recent theoretical, numerical and experimental developments in the field of frustrated spin systems. The first edition of the book appeared in 2005. In this edition, more recent works until 2012 are reviewed. It contains nine chapters written by researchers who have actively contributed to the field. Many results are from recent works of the authors.The book is intended for postgraduate students as well as researchers in statistical physics, magnetism, materials science and various domains where real systems can be described with the spin language. Explicit demonstrations of formulas and full arguments leading to important results are given where it is possible to do so."
Download or read book Spin Wave Technology written by George J. Bugh and published by Vasant Corporation. This book was released on 2002 with total page 268 pages. Available in PDF, EPUB and Kindle. Book excerpt: 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.
Download or read book Spin Wave Confinement written by Sergej O. Demokritov and published by CRC Press. This book was released on 2017-09-07 with total page 436 pages. Available in PDF, EPUB and Kindle. Book excerpt: Since the publication of the first edition of Spin-Wave Confinement, the magnetic community’s interest in dynamic excitations in magnetic systems of reduced dimensions has been increasing. Although the concept of spin waves and their quanta (magnons) as propagating excitation of magnetic media was introduced more than 80 years ago, this field has been repeatedly bringing us fascinating new physical phenomena. The successful development of magnonics as an emerging subfield of spintronics, which considers confined spin waves as a basis for smaller, faster, more robust, and more power-efficient electronic devices, inevitably demands reduction in the sizes and dimensions of the magnetic systems being studied. The unique features of magnons, including the possibility of carrying spin information over relatively long distances, the possibility of achieving submicrometer wavelength at microwave frequencies, and controllability by electronic signal via magnetic fields, make magnonic devices distinctively suited for implementation of novel integrated electronic schemes characterized by high speed, low power consumption, and extended functionalities. Edited by S. O. Demokritov, a prominent magnonics researcher who has successfully collected the results of cutting-edge research by almost all main players in the field, this book is for everyone involved in nanotechnology, spintronics, magnonics, and nanomagnetism.
Download or read book Elements of Slow Neutron Scattering written by J. M. Carpenter and published by Cambridge University Press. This book was released on 2015-09-24 with total page 539 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book provides a comprehensive and up-to-date introduction to the fundamental theory and applications of slow-neutron scattering.
Download or read book Theory of Collective Spin Wave Modes of Interacting Ferromagnetic Spheres written by and published by . This book was released on 2004 with total page 8 pages. Available in PDF, EPUB and Kindle. Book excerpt: We formulate the theory of the collective spin wave modes of arrays of spherical particles of ferromagnetic material, under the assumption that each sphere in the array is magnetized uniformly. In addition, the intersphere interactions have their origin in the magnetic fields generated by the precessing moments, appropriate to the case where there is no direct physical contact between the spheres. The formulation is a real space analysis, and thus can be applied in principle to disordered arrangements of spheres. While our formulation is quite general, and is directly applicable to the case where both exchange and dipolar interactions influence spin motions within an individual sphere, explicit calculations are presented for the case where exchange is absent. The numerical calculations we discuss explore the collective spin wave modes of square planar arrays of spheres, and consider the case where the spheres are magnetized both perpendicular and parallel to the plane.
