Band-Ferromagnetism: Ground-State and Finite-Temperature Phenomena

3540423893......Page 1
Lecture Notes in Physics......Page 2
Online Version/ LNP Homepage......Page 3
Band-Ferromagnetism......Page 4
Preface......Page 6
Part II Finite-Temperature Electronic Structure......Page 7
Part IV Low-Dimensional Systems......Page 8
Part V Understanding Spectroscopies......Page 9
Introduction......Page 10
Ground State Properties......Page 12
Finite Temperature Electronic Structure......Page 13
Dimension-Reduced Systems......Page 14
Understanding of Spectroscopies......Page 15
1 Exchange Versus Correlations......Page 16
2 Hamilton Operator......Page 17
3.1 Variational Ground-State Energy......Page 18
3.2 Spinwaves......Page 20
4.1 Ground-State Properties......Page 22
4.2 Spinwave Dispersions......Page 23
5.1 Discrepancies Between Experiment and SDFT......Page 24
5.2 Present Status of the Gutzwiller-DFT......Page 25
5.3 Comparison to Experiments......Page 29
6 Conclusions and Outlook......Page 31
References......Page 32
1 Introduction......Page 34
2 Magnetic Anisotropy Energy (MAE)......Page 36
2.1 Intrinsic Anisotropy K......Page 37
2.2 Dipolar (Shape)Anisotropy......Page 42
2.3 Angular and Temperature Dependence of the MAE......Page 43
3 Anisotropic Magnetic Moments......Page 46
3.1 g-Tensor......Page 48
3.2 X-ray Magnetic Circular Dichroism at 3d L-Edges......Page 49
Acknowledgment......Page 50
References......Page 51
1 Introduction......Page 53
2 Magneto-Crystalline Anisotropy and Ground-State Moments......Page 54
3 The X-Ray Resonant Magnetic Scattering Amplitude......Page 55
4 Applications......Page 58
4.1 Magnetic Depth Profile of Ultrathin FePd Films......Page 59
4.2 Interface Magneto-Crystalline Anisotropy of Fe/CeH_2 Multilayers......Page 61
5 Summary and Outlook......Page 64
References......Page 65
1 Introduction......Page 67
2.1 FLAPW Approach......Page 68
2.2 Spin-Orbit Coupling and Magneto-crystalline Anisotropy......Page 69
3 Results and Discussion......Page 70
3.1 Cubic Transition Metal Bulks......Page 71
3.2 Fe,Co and Ni Alloys......Page 72
3.3 Rare Earth Intermetallic Compounds......Page 75
References......Page 77
1 Introduction......Page 79
2 Computational Technique......Page 82
3Exchange Interactions......Page 86
4 Computational Results......Page 88
Appendix......Page 92
5 Conclusions......Page 94
References......Page 95
1 Introduction......Page 98
2 Experimental......Page 99
3.1 Conservation Laws in Photoemission......Page 101
3.2 k-Space Mapping......Page 104
4.1 The Temperature Dependence of the Exchange Splitting in Nickel......Page 106
4.2 Influence of a Commensurate Insulator on the Magnetism of Nickel......Page 108
References......Page 112
1 Introduction......Page 115
2 Correlation Effects in Valence Band Spectra of Ni......Page 118
3 Temperature Dependence of Ni(110) Valence Bands......Page 122
4 Temperature Dependence of Valence Band Satellites of Ni......Page 125
5 Conclusion and Outlook......Page 127
References......Page 128
Spin Fluctuations in Itinerant Electron Systems......Page 130
1 Fluctuations of a Thermodynamical Variable......Page 131
2 Fluctuations of the Magnetic Moment......Page 132
3 The Specific Heat of the Spin Fluctuations......Page 137
4 Magneto-Volume Coupling......Page 138
5 Comparing the Spin-Fluctuation-and the Stoner-Model......Page 139
6 The Landau-Ginzburg Model for Spin Fluctuations......Page 140
References......Page 146
2 Stoner-Wohlfarth Theory at Non-zero Temperatures......Page 147
3.1 Incommensurate Spiral Structure......Page 150
3.2 How to Treat Noncollinear Structures in Density Functional Theory......Page 152
3.3 Magnons......Page 153
4 Spin Fluctuations......Page 154
4.1 Hamiltonian......Page 155
4.2 Thermodynamics......Page 156
5 Conclusion......Page 160
References......Page 161
1 Introduction......Page 162
2 Spin Fluctuation Theory......Page 163
3.1 Spin Susceptibility......Page 165
3.2 Resistivity......Page 166
3.3 Specific Heat......Page 167
3.6 Experimental Results......Page 168
4 Quantum to Classical Crossover for α ≠ 0......Page 169
6 Conclusion......Page 174
References......Page 175
1 Introduction......Page 177
2 Theory for the Dynamics of the Magnetization in Transition-Metals at Nonequilibrium......Page 178
3.1 T_el(t)......Page 185
3.3 Magnetooptics......Page 186
Summary......Page 189
References......Page 190
1 I troduction......Page 192
2 Dynamical Mean-Field Theory......Page 193
3 The One-Band Hubbard Model......Page 194
3.1 Routes to Ferromagnetism......Page 195
3.2 Frustrated Lattices......Page 196
3.3 Additional Interactions......Page 200
4 Band Degeneracy and Local Exchange......Page 202
5 Conclusion and Outlook......Page 205
References......Page 206
1 Introduction......Page 209
2 Hubbard Model Basic Features......Page 210
3 Analytical Approaches......Page 215
3.1 Spin-Dependent Band Shift......Page 216
3.2 Quasiparticle Damping......Page 218
3.3 Weak-Coupling Behaviour......Page 222
4 Discussion......Page 223
References......Page 225
1 Superexchange Interactions and Orbital Order......Page 227
2 Stoner Instability in the Orbital Model......Page 231
3 Double Exchange in the Correlated e_g Band......Page 237
Acknowledgmen......Page 240
References......Page 241
1 Introduction......Page 242
2 MAE, Magnetostriction and Magneto-elastic Coupling......Page 243
3 Theoretical Method......Page 244
3.1 Different Types of k-Space Integration......Page 245
3.2 The FP-LMTO Method......Page 246
3.3 Defining the LMTO Basis Functions......Page 247
3.4 Calculating the Matrix Elements......Page 249
3.5 Surface Slab Calculations......Page 250
4 Spin and Orbital Pairing......Page 253
5 Force Theorem and MAE......Page 255
6 Thin Film Magnetism......Page 257
7 Magnetostriction of Fe, Co and Ni......Page 260
Acknowledgments......Page 263
References......Page 264
1 Dimension-Reduced Band Ferromagnets......Page 266
2 Bulk-Derived Electronic States......Page 267
3 Surface-Derived Electronic States......Page 270
4 Surface-State Spectroscopy......Page 271
5 The Closed-Packed Surfaces of Fe, Co, and Ni......Page 273
5.1 Ni(111)......Page 274
5.2 Co(0001)......Page 276
5.3 Fe(110)......Page 277
6 Conclusion......Page 279
References......Page 280
1 Introduction......Page 282
2 Experimental Details......Page 284
3 Results and Discussion......Page 285
Acknowledgments......Page 293
References......Page 294
1 Introduction......Page 296
2 Theoretical Discussion......Page 298
2.1 The Microwave Response of an Isolated Ferromagnetic Nanowire......Page 303
3.1 The Nature of the Spin Wave Modes......Page 307
3.2 The Microwave Response of Conducting Ferromagnetic Nanowires......Page 311
4 Concluding Remarks......Page 316
References......Page 318
1 Introduction......Page 319
2.1 Spin Motion of the Electron Beam......Page 320
2.2 The Torque Acting on the Magnetization by Spin Injection......Page 322
3.1 Experimental Setup......Page 324
3.2 Samples......Page 326
4 Experimental Results for Fe, Co and Ni......Page 327
5 Precessional Magnetization Reversal Induced by a Spin-Polarized Current......Page 332
6.2 Measurements in Reflection Geometry......Page 334
References......Page 335
1 Introduction......Page 337
2 One-Step Description of Photoemission Spectroscopy......Page 339
3.1 MLD in Valence Band Photoemission from Co(0001)......Page 343
3.2 Core-Level MCD from the Fe-3p States......Page 346
4 Summary and Outlook......Page 348
References......Page 349
1 Basic Electron Spectroscopies......Page 352
2 Theory......Page 354
3 APS for Band Ferromagnets......Page 357
4 Appearance-Potential Spectra of Nickel......Page 360
5 Conclusions......Page 365
References......Page 366
1 Introduction......Page 367
2 Effective Single-Particle Hamiltonian for Magnetic Solids Including Spin-Orbit Coupling......Page 368
3 Spin-Orbit-Induced Properties via Perturbation Theory......Page 369
4 Spin-Orbit-Induced Orbital Magnetic Moment......Page 371
5 Fano Effect in Magnetic Dichroism Photoemission......Page 373
6 Magnetic Dichroism in X-Ray Absorption......Page 376
References......Page 380
1 Introduction......Page 382
2 Time Scales for and Electronic Degrees of Freedom......Page 384
3 Neutron Scattering and Lattice Induced Magnetic Moment Modulation......Page 385
References......Page 390