磁性材料 第2版 英文PDF电子书下载

Ⅰ Basics 3

1 Review of basic magnetostatics 3

1.1 Magnetic field 4

1.1.1 Magnetic poles 4

1.1.2 Magnetic flux 6

1.1.3 Circulating currents 6

1.1.4 Ampère's circuital law 7

1.1.5 Biot-Savart law 8

1.1.6 Field from a straight wire 8

1.2 Magnetic moment 10

1.2.1 Magnetic dipole 11

1.3 Definitions 11

Homework 12

2 Magnetization and magnetic materials 14

2.1 Magnetic induction and magnetization 14

2.2 Flux density 15

2.3 Susceptibility and permeability 16

2.4 Hysteresis loops 18

2.5 Definitions 19

2.6 Units and conversions 19

Homework 20

3 Atomic origins of magnetism 22

3.1 Solution of the Schr？dinger equation for a free atom 22

3.1.1 What do the quantum numbers represent? 25

3.2 The normal Zeeman effect 27

3.3 Electron spin 30

3.4 Extension to many-electron atoms 31

3.4.1 Pauli exclusion principle 32

3.5 Spin-orbit coupling 32

3.5.1 Russell-Saunders coupling 32

3.5.2 Hund's rules 34

3.5.3 jj coupling 35

3.5.4 The anomalous Zeeman effect 35

Homework 37

Diamagnetism 38

4.1 Observing the diamagnetic effect 38

4.2 Diamagnetic susceptibility 39

4.3 Diamagnetic substances 41

4.4 Uses of diamagnetic materials 42

4.5 Superconductivity 42

4.5.1 The Meissner effect 43

4.5.2 Critical field 44

4.5.3 Classification of superconductors 44

4.5.4 Superconducting materials 44

4.5.5 Applications for superconductors 46

Homework 46

5 Paramagnetism 48

5.1 Langevin theory of paramagnetism 49

5.2 The Curie-Weiss law 52

5.3 Quenching of orbital angular momentum 54

5.4 Pauli paramagnetism 55

5.4.1 Energy bands in solids 56

5.4.2 Free-electron theory of metals 58

5.4.3 Susceptibility of Pauli paramagnets 60

5.5 Paramagnetic oxygen 62

5.6 Uses of paramagnets 63

Homework 64

6 Interactions in ferromagnetic materials 65

6.1 Weiss molecular field theory 66

6.1.1 Spontaneous magnetization 66

6.1.2 Effect of temperature on magnetization 67

6.2 Origin of the Weiss molecular field 69

6.2.1 Quantum mechanics of the He atom 70

6.3 Collective-electron theory of ferromagnetism 73

6.3.1 The Slater-Pauling curve 76

6.4 Summary 76

Homework 78

7 Ferromagnetic domains 79

7.1 Observing domains 79

7.2 Why domains occur 81

7.2.1 Magnetostatic energy 81

7.2.2 Magnetocrystalline energy 82

7.2.3 Magnetostrictive energy 84

7.3 Domain walls 85

7.4 Magnetization and hysteresis 87

Homework 92

8 Antiferromagnetism 96

8.1 Neutron diffraction 97

8.2 Weiss theory of antiferromagnetism 101

8.2.1 Susceptibility above TN 102

8.2.2 Weiss theory at TN 103

8.2.3 Spontaneous magnetization below TN 103

8.2.4 Susceptibility below TN 103

8.3 What causes the negative molecular field? 107

8.4 Uses of antiferromagnets 110

Homework 112

9 Ferrimagnetism 113

9.1 Weiss theory of ferrimagnetism 114

9.1.1 Weiss theory above TC 115

9.1.2 Weiss theory below TC 117

9.2 Ferrites 120

9.2.1 The cubic ferrites 120

9.2.2 The hexagonal ferrites 124

9.3 The garnets 125

9.4 Half-metallic antiferromagnets 126

Homework 127

10 Summary of basics 130

10.1 Review of types of magnetic ordering 130

10.2 Review of physics determining types of magnetic ordering 131

Ⅱ Magnetic phenomena 135

11 Anisotropy 135

11.1 Magnetocrystalline anisotropy 135

11.1.1 Origin of magnetocrystalline anisotropy 136

11.1.2 Symmetry of magnetocrystalline anisotropy 138

11.2 Shape anisotropy 139

11.2.1 Demagnetizing field 139

11.3 Induced magnetic anisotropy 141

11.3.1 Magnetic annealing 141

11.3.2 Roll anisotropy 142

11.3.3 Explanation for induced magnetic anisotropy 142

11.3.4 Other ways of inducing magnetic anisotropy 143

Homework 144

12 Nanoparticles and thin films 145

12.1 Magnetic properties of small particles 145

12.1.1 Experimental evidence for single-domain 147

particles 147

12.1.2 Magnetization mechanism 147

12.1.3 Superparamagnetism 148

12.2 Thin-film magnetism 152

12.2.1 Structure 152

12.2.2 Interfaces 153

12.2.3 Anisotropy 153

12.2.4 How thin is thin? 154

12.2.5 The limit of two-dimensionality 154

13 Magnetoresistance 156

13.1 Magnetoresistance in normal metals 157

13.2 Magnetoresistance in ferromagnetic metals 158

13.2.1 Anisotropic magnetoresistance 158

13.2.2 Magnetoresistance from spontaneous magnetization 159

13.2.3 Giant magnetoresistance 160

13.3 Colossal magnetoresistance 164

13.3.1 Superexchange and double exchange 164

Homework 168

14 Exchange bias 169

14.1 Problems with the simple cartoon mechanism 171

14.1.1 Ongoing research on exchange bias 172

14.2 Exchange anisotropy in technology 173

Ⅲ Device applications and novel materials 177

15 Magnetic data storage 177

15.1 Introduction 177

15.2 Magnetic media 181

15.2.1 Materials used in magnetic media 181

15.2.2 The other components of magnetic hard disks 183

15.3 Write heads 183

15.4 Read heads 185

15.5 Future of magnetic data storage 186

16 Magneto-optics and magneto-optic recording 189

16.1 Magneto-optics basics 189

16.1.1 Kerr effect 189

16.1.2 Faraday effect 191

16.1.3 Physical origin of magneto-optic effects 191

16.2 Magneto-optic recording 193

16.2.1 Other types of optical storage, and the future of magneto-optic recording 196

17 Magnetic semiconductors and insulators 197

17.1 Exchange interactions in magnetic semiconductors and insulators 198

17.1.1 Direct exchange and superexchange 199

17.1.2 Carrier-mediated exchange 199

17.1.3 Bound magnetic polarons 200

17.2 Ⅱ-Ⅵ diluted magnetic semiconductors-(Zn,Mn)Se 201

17.2.1 Enhanced Zeeman splitting 201

17.2.2 Persistent spin coherence 202

17.2.3 Spin-polarized transport 203

17.2.4 Other architectures 204

17.3 Ⅲ-Ⅴ diluted magnetic semiconductors-(Ga,Mn)As 204

17.3.1 Rare-earth-group-V compounds-ErAs 207

17.4 Oxide-based diluted magnetic semiconductors 208

17.5 Ferromagnetic insulators 210

17.5.1 Crystal-field and Jahn-Teller effects 210

17.5.2 YTiO3 and SeCuO3 211

17.5.3 BiMnO3 213

17.5.4 Europium oxide 214

17.5.5 Double perovskites 215

17.6 Summary 215

18 Multiferroics 216

18.1 Comparison of ferromagnetism and other types of ferroic ordering 216

18.1.1 Ferroelectrics 216

18.1.2 Ferroelastics 219

18.1.3 Ferrotoroidics 220

18.2 Multiferroics that combine magnetism and ferroelectricity 221

18.2.1 The contra-indication between magnetism and ferroelectricity 222

18.2.2 Routes to combining magnetism and ferroelectricity 223

18.2.3 The magnetoelectric effect 225

18.3 Summary 228

Epilogue 229

Solutions to selected exercises 230

References 262

Index 270