Dionne Magnetic Oxides

1. Auflage 2010
ISBN: 978-1-4419-0054-8
Verlag: Springer
Format: PDF
Kopierschutz: 1 - PDF Watermark

E-Book, Englisch, 466 Seiten

Magnetic Oxides offers a cohesive up-to-date introduction to magnetism in oxides. Emphasizing the physics and chemistry of local molecular interactions essential to the magnetic design of small structures and thin films, this volume provides a detailed view of the building blocks for new magnetic oxide materials already advancing research and development of nano-scale technologies. Clearly written in a well-organized structure, readers will find a detailed description of the properties of magnetic oxides through the prism of local interactions as an alternative to collective electron concepts that are more applicable to metals and semiconductors. Researchers will find Magnetic Oxides a valuable reference.      

Autoren/Hrsg.

Dionne, Gerald F.

Inhaltsverzeichnis

1;Preface;6
2;Contents;8
3;1 Introductory Magnetism;13
3.1;1.1 Fundamental Concepts and Definitions;13
3.1.1;1.1.1 Basic Electrostatics;14
3.1.2;1.1.2 Basic Magnetostatics;15
3.1.3;1.1.3 Demagnetization in Uniformly Magnetized Bodies;16
3.1.4;1.1.4 Domains in Partially Magnetized Bodies;18
3.2;1.2 Induced Magnetism;20
3.2.1;1.2.1 Diamagnetism and Paramagnetism;20
3.2.2;1.2.2 Temperature Dependence of Susceptibility;23
3.3;1.3 Spontaneous Magnetism;27
3.3.1;1.3.1 Classical Ferromagnetism and Antiferromagnetism;27
3.3.2;1.3.2 Solutions of the Brillouin–Weiss Equation;28
3.3.3;1.3.3 Quantum Origins of the Molecular Field;31
3.3.4;1.3.4 The Ising Approximation;36
3.4;1.4 Gyromagnetism;37
3.4.1;1.4.1 Larmor Precession and Resonance;38
3.4.2;1.4.2 Phenomenological Relaxation Theory;39
3.4.3;1.4.3 Complex Susceptibility Theory;41
3.4.4;1.4.4 Resonance Line Shapes;45
3.5;Appendix 1A Spin–Lattice Contribution to Linewidth;46
3.6;Appendix 1A Spin–Lattice Contribution to Linewidth;45
4;2 Magnetic Ions in Oxides;48
4.1;2.1 The Transition Metals;48
4.1.1;2.1.1 The Periodic Table;49
4.1.2;2.1.2 Iron Group 3dn Ions;51
4.1.3;2.1.3 Rare Earth 4fn Ions;53
4.1.4;2.1.4 4dn and 5dn Ions;53
4.2;2.2 Oxygen Coordinations;54
4.2.1;2.2.1 Crystal Systems and Point Groups;55
4.2.2;2.2.2 Cubic Symmetry;56
4.2.3;2.2.3 Lower Symmetries;58
4.3;2.3 Crystal Electric Fields;59
4.3.1;2.3.1 Angular Momentum States;60
4.3.2;2.3.2 Crystal Field Hamiltonian;61
4.3.3;2.3.3 Hierarchy of Perturbations;65
4.3.4;2.3.4 Weak-Field Solutions;66
4.3.5;2.3.5 Group Theory and Lower Symmetry;75
4.3.6;2.3.6 Strong Field Solutions and Term Diagrams;79
4.3.7;2.3.7 Rare-Earth Ion Solutions;82
4.4;2.4 Orbital Energy Stabilization;84
4.4.1;2.4.1 One-Electron Model;84
4.4.2;2.4.2 High- and Low-Spin States;86
4.4.3;2.4.3 Orbit–Lattice Stabilization (Jahn–Teller Effects);90
4.4.4;2.4.4 Spin–Orbit–Lattice Stabilization;93
4.5;2.5 Covalent Stabilization;99
4.5.1;2.5.1 Molecular-Orbital Theory;100
4.5.2;2.5.2 Determinant Method;102
4.5.3;2.5.3 and Bonds and the Molecular Orbital Diagram;106
4.5.4;2.5.4 Valence Bond Method;110
4.6;Appendix 2A Homonuclear Molecule Ion;113
4.7;Appendix 2A Homonuclear Molecule Ion;112
4.8;Appendix 2B Valence-Bond Diatomic Molecule;114
5;3 Magnetic Exchange in Oxides;118
5.1;3.1 Interionic Magnetic Exchange;119
5.1.1;3.1.1 Molecular-Orbital Exchange Approximation;120
5.1.2;3.1.2 Valence-Bond Solutions;124
5.1.3;3.1.3 Spin Alignment in Oxides;130
5.1.4;3.1.4 Ferromagnetism by Spin Transfer;132
5.1.5;3.1.5 Goodenough–Kanamori Rules;136
5.2;3.2 Antiferromagnetism;140
5.2.1;3.2.1 Superexchange and Molecular Fields;140
5.2.2;3.2.2 Molecular Field Theory of Antiferromagnetism;142
5.2.3;3.2.3 Antiferromagnetic Spin Configurations;146
5.3;3.3 Antiferromagnetic Oxides;150
5.3.1;3.3.1 One-Metal Oxides;150
5.3.2;3.3.2 ABO3 and A2BO4 Perovskites;151
5.3.3;3.3.3 The Mixed-Valence Manganite Anomaly;154
5.4;Appendix 3A Analysis of M2+O2- Exchange Interactions;113
5.5;Appendix 3A Analysis of M2+O2- Exchange Interactions;156
5.6;Appendix 3B Curie Temperature Model for (La,Ca) MnO3;114
5.7;References;159
6;4 Ferrimagnetism;162
6.1;4.1 Ferrimagnetic Order;162
6.1.1;4.1.1 Generic Ferrimagnetic Systems;163
6.1.2;4.1.2 Molecular Field Theory of Ferrimagnetism;164
6.1.3;4.1.3 Magnetic Frustration and Spin Canting;168
6.2;4.2 Theory of Superexchange Dilution;172
6.2.1;4.2.1 Superexchange Energy Stabilization;172
6.2.2;4.2.2 Molecular Field Coefficients;175
6.2.3;4.2.3 Solution for Yttrium Iron Garnet;176
6.3;4.3 Ferrimagnetic Oxides;179
6.3.1;4.3.1 Spinel Ferrites A[B2]O4;180
6.3.2;4.3.2 Garnet Ferrites {c3}[a2](d3)O12;186
6.3.3;4.3.3 Rare-Earth Garnet Ferrites;191
6.3.4;4.3.4 Rare-Earth Canting Effect;195
6.3.5;4.3.5 Hexagonal Ferrites;201
6.3.6;4.3.6 Orthoferrites;204
6.4;Appendix 4A Molecular Field Analysis of LiZnTi Ferrite;113
6.5;Appendix 4A Molecular Field Analysis of LiZnTi Ferrite;205
6.6;Appendix 4B High-Magnetization Limits;114
6.7;Appendix 4C Brillouin Functions in Exchange Energy Format;207
6.8;Appendix 4C Brillouin Functions in Exchange Energy Format;207
7;5 Anisotropy and Magnetoelastic Properties;211
7.1;5.1 Quantum Paramagnetism of Single Ions;212
7.1.1;5.1.1 Theory of Anisotropic g Factors;212
7.1.2;5.1.2 Conventional Perturbation Solutions;215
7.1.3;5.1.3 The Spin Hamiltonian for 3dn Ions;219
7.1.4;5.1.4 The Crystal-Field Hamiltonian for 4fn Ions;220
7.2;5.2 Anisotropy of Single Ions;222
7.2.1;5.2.1 3d1 and 3d6 D-State Triplet;223
7.2.2;5.2.2 3d4 and 3d9 D-State Doublet (J–T Effect);227
7.2.3;5.2.3 3d2 and 3d7 F-State Triplet;229
7.2.4;5.2.4 3d3 and 3d8 F-State Singlet;230
7.2.5;5.2.5 3d5 S-State Singlet;232
7.2.6;5.2.6 4fn Ion Anisotropy;236
7.3;5.3 Magnetocrystalline Anisotropy and Magnetostriction;238
7.3.1;5.3.1 Phenomenological Anisotropy Theory;239
7.3.2;5.3.2 Phenomenological Magnetostriction Theory;241
7.3.3;5.3.3 Dipolar Pair Model of Magnetic Anisotropy;244
7.3.4;5.3.4 Single-Ion Model of Ferrimagnetic Anisotropy;246
7.3.5;5.3.5 Cooperative Single-Ion Effects: Anisotropy;251
7.3.6;5.3.6 Cooperative Single-Ion Effects: Magnetostriction;256
7.4;5.4 Magnetization Process and Hysteresis;260
7.4.1;5.4.1 Initial Permeability and Coercivity;261
7.4.2;5.4.2 Anisotropy Field and Remanence Ratio;264
7.4.3;5.4.3 Approach to Saturation;266
7.4.4;5.4.4 Demagnetization and Permanent Magnets;268
7.5;Appendix 5A Four-Level Degenerate Perturbation Solution for d1;113
7.6;Appendix 5A Four-Level Degenerate Perturbation Solution for d1;270
7.7;Appendix 5B T2g Solution for d1 in an Exchange Field;114
7.8;Appendix 5B T2g Solution for d1 in an Exchange Field;273
7.9;Appendix 5C Orbital States of d5 in a Cubic Field;207
7.10;Appendix 5D Angular Dependence of Cubic Anisotropy Fields;277
7.11;References;279
8;6 Electromagnetic Properties;282
8.1;6.1 Magnetic Relaxation;283
8.1.1;6.1.1 Nonresonant Longitudinal Relaxation;283
8.1.2;6.1.2 Quantum Mechanisms of Spin–Lattice Relaxation;287
8.1.3;6.1.3 Perturbation Theories of Spin–Phonon Interaction;295
8.2;6.2 Gyromagnetic Resonance and Relaxation;296
8.2.1;6.2.1 Paramagnetic Resonance;297
8.2.2;6.2.2 Ferromagnetic Resonance;301
8.2.3;6.2.3 Uniform Precession Damping;304
8.2.4;6.2.4 Inhomogeneous Resonance Line Broadening;306
8.2.5;6.2.5 Fast-Relaxing Ion Effects;309
8.2.6;6.2.6 The Exchange Isolation Effect;315
8.3;6.3 Exchange-Coupled Modes (Spin Waves);316
8.3.1;6.3.1 Uniform Precession Decoherence (Degenerate Spin Waves);316
8.3.2;6.3.2 Instability Threshold (Classical Approximation);320
8.3.3;6.3.3 Instability Threshold (Nonlinear Spin Waves);324
8.3.4;6.3.4 Magnetostatic Modes;326
8.4;6.4 Permeability and Propagation;327
8.4.1;6.4.1 Low-Frequency Longitudinal Permeability;327
8.4.2;6.4.2 High-Frequency Transverse Limits;331
8.4.3;6.4.3 Snoek's Law Considerations;333
8.4.4;6.4.4 Circular Polarization and Nonreciprocal Properties;336
8.4.5;6.4.5 Linear Polarization and Faraday Rotation;341
8.5;Appendix 6A Transverse Permeability Tensor;113
8.6;Appendix 6B Classical Instability Threshold;114
8.7;Appendix 6B Classical Instability Threshold;345
8.8;Appendix 6C Domain Wall Susceptibility Equation;207
8.9;References;348
9;7 Magneto-Optical Properties;352
9.1;7.1 Infrared Exchange Resonance;353
9.1.1;7.1.1 Classical Precession Model;353
9.1.2;7.1.2 Quantum Spin Transition Model;355
9.1.3;7.1.3 Experimental Exchange Spectra;360
9.2;7.2 Combined Permeability and Permittivity;361
9.2.1;7.2.1 The [] [] Tensor Solutions;361
9.2.2;7.2.2 Propagation Parameters and Faraday Rotation;362
9.3;7.3 Magneto-Optical Spectra;364
9.3.1;7.3.1 Electric-Dipole Transitions;364
9.3.2;7.3.2 Yttrium Iron Garnet Spectra (Paramagnetic);369
9.3.3;7.3.3 Iron Garnets with Bismuth Ions (Diamagnetic);375
9.3.4;7.3.4 Fe3+–Bi3+ Hybrid Excited States;380
9.3.5;7.3.5 Intersublattice Transitions and the S=0 Rule;385
9.4;Appendix 7A Magnetic Circular Birefringence and Dichroism;113
9.5;Appendix 7A Magnetic Circular Birefringence and Dichroism;389
9.6;References;391
10;8 Spin Transport Properties;394
10.1;8.1 Polarons and Charge Transfer;395
10.1.1;8.1.1 Transfer Among Equivalent Energy Sites (Small Polarons);397
10.1.2;8.1.2 Transfer to Higher Energy Sites (Large Polarons);398
10.1.3;8.1.3 Transfer by Covalent Tunneling;401
10.1.4;8.1.4 The Holstein Polaron Theory;403
10.2;8.2 Metallic Oxides with Polarized Spins;405
10.2.1;8.2.1 Simple Oxides;406
10.2.2;8.2.2 Complex Oxides;406
10.2.3;8.2.3 Classical Resistivity–Temperature Model;409
10.3;8.3 Magnetoresistance in Oxides (CMR);410
10.3.1;8.3.1 Manganese-Ion Exchange Interactions;411
10.3.2;8.3.2 Magnetoresistivity-Temperature Model;414
10.3.3;8.3.3 Dilute Magnetic Oxides;419
10.4;8.4 Superconductivity in Oxides;422
10.4.1;8.4.1 Classical Foundations;422
10.4.1.1;8.4.1.1 The London Equations;422
10.4.1.2;8.4.1.2 The Macroscopic Molecule;425
10.4.1.3;8.4.1.3 Nonlocal Considerations;426
10.4.1.4;8.4.1.4 Carrier Statistics;427
10.4.2;8.4.2 Zero-Spin Polarons and Magnetic Frustration;428
10.4.3;8.4.3 Large-Polaron Superconductivity;432
10.4.4;8.4.4 Normal Resistivity and Critical Temperature;435
10.4.5;8.4.5 Layered Cuprate Superconductors;439
10.5;8.5 Supercurrents and Magnetic Fields;448
10.5.1;8.5.1 Supercurrent Formation;448
10.5.2;8.5.2 Condensation Energy;451
10.5.3;8.5.3 London Penetration Depth;452
10.5.4;8.5.4 Critical Magnetic Field;454
10.5.5;8.5.5 Critical Current Density;456
10.5.6;8.5.6 Coherence Length;459
10.5.7;8.5.7 Type-II Superconductors;461
10.6;Appendix 8A Magnetic Levitation;113
10.7;Appendix 8A Magnetic Levitation;464
10.8;References;465
11;Index;469