1 The Magnetic Susceptibility 1
1.1 The Magnetic Moment 2
1.2 The Magnetization 7
1.3 The Generalized Susceptibility 12
1.3.1 The Kramers-Kronig Relations 14
1.3.2 The Fluctuation-Dissipation Theorem 15
1.3.3 Onsager Relation 20
1.4 Second Quantization 21
1.4.1 Example:The Degenerate-Electron Gas 26
1.4.2 Example:The Zeeman Interaction 29
2 The Magnetic Hamiltonian 33
2.1 The Dirac Equation 33
2.2 Sources of Fields 35
2.2.1 Uniform External Field 35
2.2.2 The Electric Quadrupole Field 36
2.2.3 The Magnetic Dipole(Hyperfine)Field 41
2.2.4 Other Electrons on the Same Ion 43
2.2.5 Crystalline Electric Fields 44
2.2.6 Dipole-Dipole Interaction 50
2.2.7 Direct Exchange 51
2.2.8 Superexchange 58
2.2.9 Molecular Magnets 62
2.2.10 Double Exchange 65
2.2.11 Exchange on a Surface 66
2.3 The Spin Hamiltonian 67
2.3.1 Transition-Metal Ions 67
2.3.2 Rare-Earth Ions 75
2.3.3 Semiconductors 77
3 The Static Susceptibility of Noninteracting Systems 85
3.1 Localized Moments 85
3.1.1 Diamagnetism 88
3.1.2 Paramagnetism of Transition-Metal Ions 89
3.1.3 Paramagnetism of Rare-Earth Ions 91
3.2 Metals 94
3.2.1 Landau Diamagnetism 94
3.2.2 The de Haas-van Alphen Effect 98
3.2.3 Quantized Hall Conductance 102
3.2.4 Pauli Paramagnetism 106
3.3 Measurement of the Susceptibility 112
3.4 Local Moments in Metals 115
3.4.1 Virtual Bound States 116
3.4.2 Anderson's Theory of Moment Formation 119
3.4.3 The Kondo Effect 124
4 The Static Susceptibility of Interacting Systems:Local Moments 133
4.1 High Temperatures 135
4.2 Low Temperatures 146
4.3 Temperatures Near Tc 149
4.4 Landau Theory of Second-Order Transitions 153
4.5 Critical Phenomena 154
4.5.1 Order in 2D 155
4.6 Stoner-Wohlfarth Model 159
4.7 Dynamic Coercivity 162
4.8 Magnetic Viscosity 165
5 The Static Susceptibility of Interacting Systems:Metals 169
5.1 Fermi Liquid Theory 169
5.2 Heavy Fermion Systems 176
5.3 Itinerant Magnetism 177
5.3.1 The Stoner Model 177
5.3.2 The Hubbard Model 187
6 The Dynamic Susceptibility of Weakly Interacting Systems:Local Moments 193
6.1 Equation of Motion 193
6.2 The Bloch Equations 197
6.3 Resonance Line Shape 202
6.3.1 The Method of Moments 202
6.3.2 The Relaxation-Function Method 206
6.3.3 Spin Diffusion 210
6.4 Spin Echoes 211
6.4.1 Measurement of T1 211
6.4.2 Calculation of T1 213
7 The Dynamic Susceptibility of Weakly Interacting Systems:Metals 219
7.1 Paramagnons 221
7.2 Fermi Liquid Theory 223
7.3 Conduction-Electron Spin Resonance 228
7.4 Spin Waves 230
7.5 Local Moments in Metals 231
7.6 Faraday Effect 235
8 The Dynamic Susceptibility of Strongly Interacting Systems 237
8.1 Broken Symmetry 237
8.2 Insulators 238
8.2.1 Spin-Wave Theory 240
8.2.2 Coherent Magnon State 248
8.2.3 Magnetostatic Modes 249
8.2.4 Solitons 250
8.2.5 Thermal Magnon Effects 253
8.2.6 Nonlinear Processes 255
8.2.7 Chaos 259
8.2.8 Optical Processes 262
8.3 High Temperatures 266
8.4 Micromagnetics 269
8.4.1 Magnetic Force Microscope 270
8.4.2 Phenomenological Damping 273
8.5 Metals 274
9 Thin Film Systems 281
9.1 Interfaces 281
9.1.1 Exchange Bias 281
9.1.2 Biquadratic Exchange 284
9.2 Trilayers 285
9.2.1 The RKKY Ineraction 286
9.2.2 Quantum Well Model 289
9.2.3 Giant Magnetoresistance(GMR) 292
9.2.4 Tunneling 300
9.2.5 Spin Transfer 306
9.2.6 Spin Hall Effect 310
10 Neutron Scattering 315
10.1 Neutron Scattering Cross Section 315
10.2 Nuclear Scattering 317
10.2.1 Bragg Scattering 318
10.2.2 Scattering of Phonons 320
10.3 Magnetic Scattering 324
10.3.1 Bragg Scattering 328
10.3.2 Spin Dynamics 333
10.4 Example:Manganese Oxides 337
10.5 Example:Quantum Phase Transitions 341
References 345
Index 355