Weinberger Magnetic Anisotropies in Nanostructured Matter

Erscheinungsjahr 2010
ISBN: 978-1-4200-7266-2
Verlag: Taylor & Francis
Format: PDF
Kopierschutz: Adobe DRM (»Systemvoraussetzungen)

E-Book, Englisch, 310 Seiten

Reihe: Condensed Matter Physics

One of the Top Selling Physics Books according to YBP Library Services
Magnetic Anisotropies in Nanostructured Matter presents a compact summary of all the theoretical means to describe magnetic anisotropies and interlayer exchange coupling in nanosystems. The applications include free and capped magnetic surfaces, magnetic atoms on metallic substrates, nanowires, nanocontacts, and domain walls. Some applications also deal with temperature-dependent effects and ab initio magnetization dynamics.

The author clarifies parallel and antiparallel, the distinction between classical spin vectors and spinors, and the actual form of spin–orbit interactions, before showing how symmetry can provide the formal tools to properly define magnetic structures. After these introductory chapters, the book presents methods to describe anisotropic physical properties of magnetic nanostructures. It then focuses on magnetic anisotropy energies, exchange and Dzyaloshinskii–Moriya interactions, temperature-dependent effects, spin dynamics, and related properties of systems nanostructured in one and two dimensions. The book also discusses how methods of describing electric and magneto-optical properties are applied to magnetic nanostructured matter. It concludes with an outlook on emerging magnetic anisotrophic effects.

Written by a leading researcher with over 35 years of experience in the field, this book examines the theory and modeling of magnetic anisotropies in nanostructured materials. It shows how these materials are used in a range of applications.

Zielgruppe

Researchers and graduate students in physics and engineering.

Autoren/Hrsg.

Weinberger, Peter

Fachgebiete

• Technische Wissenschaften Maschinenbau | Werkstoffkunde Maschinenbau

Inhaltsverzeichnis

Introduction
Preliminary Considerations
Parallel, antiparallel, collinear, and noncollinear
Characteristic volumina
"Classical" spin vectors and spinors
The famous spin–orbit interaction
Symmetry Considerations
Translational invariance
Rotational invariance
Colloquial or parent lattices
Tensorial products of spin and configuration
Cell-dependent potentials and exchange fields
Magnetic configurations
Green’s Functions and Multiple Scattering
Resolvents and Green’s functions
The Dyson equation
Scaling transformations
Integrated density of states
Superposition of individual potentials
The scattering path operator
Angular momentum and partial wave representations
Single particle Green’s function
Symmetry aspects
Charge and magnetization densities
Changing the orientation of the magnetization
Screening transformations
The embedded cluster method
The Coherent Potential Approximation
Configurational averages
Restricted ensemble averages
The coherent potential approximation
The single-site coherent potential approximation
Complex lattices and layered systems
Remark with respect to systems nanostructured in two dimensions
Calculating Magnetic Anisotropy Energies
Total energies
The magnetic force theorem
Magnetic dipole–dipole interactions
Exchange and Dzyaloshinskii–Moriya Interactions
The free energy and its angular derivatives
An intermezzo: classical spin Hamiltonians
Relations to relativistic multiple scattering theory
The Disordered Local Moment Method (DLM)
The relativistic DLM method for layered systems
Approximate DLM approaches
Spin Dynamics
The phenomenological Landau–Lifshitz–Gilbert equation
The semiclassical Landau–Lifshitz equation
Constrained density functional theory
The semiclassical Landau–Lifshitz–Gilbert equation
First principles spin dynamics for magnetic systems nanostructured in two dimensions
The Multiple Scattering Scheme
The quantum mechanical approach
Methodological aspects in relation to magnetic anisotropies
Physical properties related to magnetic anisotropies
Nanostructured in One Dimension: Free and Capped Magnetic Surfaces
Reorientation transitions
Trilayers, interlayer exchange coupling
Temperature dependence
A short summary
Nanostructured in One Dimension: Spin Valves
Interdiffusion at the interfaces
Spin valves and noncollinearity
Switching energies and the phenomenological Landau–Lifshitz–Gilbert equation
Heterojunctions
Summary
Nanostructured in Two Dimensions: Single Atoms, Finite Clusters, and Wires
Finite clusters
Finite wires and chains of magnetic atoms
Aspects of noncollinearity
Nanostructured in Two Dimensions: Nanocontacts, Local Alloys
Quantum corrals
Magnetic adatoms and surface states
Nanocontacts
Local alloys
Summary
A Mesoscopic Excursion: Domain Walls
Theory of Electric and Magneto-Optical Properties
Linear response theory
Kubo equation for independent particles
Electric transport—the static limit
The Kubo–Greenwood equation
Optical transport
Electric Properties of Magnetic Nanostructured Matter
The bulk anisotropic magnetoresistance (AMR)
Current-in-plane (CIP) and the giant magnetoresistance (GMR)
Current-perpendicular to the planes of atoms (CPP)
Tunneling conditions
Spin-valves
Heterojunctions
Systems nanostructured in two dimensions
Domain wall resistivities
Summary
Magneto-Optical Properties of Magnetic Nanostructured Matter
The macroscopic model
The importance of the substrate
The Kerr effect and interlayer exchange coupling
The Kerr effect and magnetic anisotropy energy
The Kerr effect in the case of repeated multilayers
How surface sensitive is the Kerr effect?
Summary
Time Dependence
Terra incognita
Pump-probe experiments
Pulsed electric fields
Spin currents and torques
Instantaneous resolvents and Green’s functions
Time-dependent multiple scattering
Physical effects to be encountered
Expectations
Afterword
Index