Preface |
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v | |
Acknowledgment |
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vii | |
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1 An Introduction to Phase Transitions and Universality |
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1 | (14) |
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2 Universal Critical Behavior from Theory and Simulations |
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15 | (8) |
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3 Background on Experimental Techniques |
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23 | (34) |
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24 | (2) |
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3.2 Specific Heat Techniques |
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26 | (6) |
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3.3 Optical Measurements of Critical Behavior |
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32 | (11) |
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3.3.1 Optical birefringence |
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33 | (2) |
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3.3.2 Specific heat critical behavior via birefringence techniques |
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35 | (6) |
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41 | (2) |
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3.3.4 Isotropic magnets and the birefringence technique |
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43 | (1) |
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43 | (1) |
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3.5 Susceptibility and Thermal Expansion |
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44 | (2) |
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3.6 Neutron and X-ray Scattering Measurements |
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46 | (2) |
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47 | (1) |
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3.6.2 Inelastic scattering |
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48 | (1) |
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3.7 The Effect of Concentration Gradients on Critical Behavior Characterizations |
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48 | (9) |
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4 Critical Behavior Experiments on Anisotropic and Isotropic Antiferomagnets |
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57 | (104) |
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58 | (4) |
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4.1.1 D = 3 Anisotropic crystals |
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58 | (3) |
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4.1.2 D = 2 Anisotropic crystals |
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61 | (1) |
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4.1.3 D = 3 Isotropic crystals |
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61 | (1) |
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4.2 Phase Diagram Measurements of Anisotropic and Isotropic Antiferromagnets |
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62 | (14) |
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4.2.1 The bicritical and tricritical points in pure and dilute anisotropic antiferromagnets |
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62 | (9) |
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4.2.2 The influence of anisotropy on the transition T/v |
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71 | (5) |
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4.3 Specific Heat Critical Behavior of Pure Ising Antiferromagnets |
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76 | (7) |
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4.3.1 D = 2 Pure Ising specific heat critical behavior |
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76 | (1) |
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4.3.2 D = 3 Pure Ising specific heat critical behavior |
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77 | (6) |
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4.4 The Order Parameter of Pure Ising Antiferromagnets |
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83 | (3) |
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4.4.1 D -- 2 Pure Ising order parameter |
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83 | (1) |
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4.4.2 D = 3 Pure Ising order parameter |
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84 | (2) |
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4.5 Neutron Scattering Critical Line Shapes of Pure Ising Antiferromagnets |
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86 | (12) |
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4.5.1 D = 2 Pure Ising neutron scattering |
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86 | (5) |
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4.5.2 D = 3 Pure Ising neutron scattering |
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91 | (7) |
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4.6 The Random-Exchange Ising Model |
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98 | (12) |
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4.6.1 D = 2 Random-exchange Ising model |
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99 | (5) |
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4.6.2 D = 3 Random-exchange Ising order parameter |
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104 | (1) |
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4.6.3 D = 3 Random-exchange Ising specific heat critical behavior |
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105 | (1) |
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4.6.4 D = 3 Random-exchange neutron scattering |
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106 | (2) |
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4.6.5 D = 3 Random-exchange dynamics |
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108 | (1) |
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4.6.6 D -- 3 Random-exchange susceptibility |
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109 | (1) |
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4.7 The Random-Field Ising Model |
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110 | (45) |
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4.7.1 D = 2 Random-field Ising critical behavior |
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115 | (3) |
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4.7.2 D = 3 Random-field Ising critical behavior |
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118 | (8) |
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4.7.3 D = 3 Random-field dynamics for x > xv |
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126 | (6) |
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4.7.4 Vacancy percolation and the stability of d = 3 antiferromagnetic long-range order |
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132 | (4) |
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4.7.5 D = 3 Random-field order parameter |
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136 | (7) |
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4.7.6 D = 3 Random-field specific heat |
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143 | (2) |
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4.7.7 D = 3 Random-field neutron scattering line shapes |
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145 | (10) |
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4.8 D = 3 XY Specific Heat Critical Behavior |
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155 | (1) |
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4.9 Experiments on Isotropic Magnets |
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156 | (5) |
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4.9.1 Optical birefringence in isotropic antiferromagnets |
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156 | (3) |
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4.9.2 The specific heat critical behavior of isotropic magnets |
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159 | (2) |
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5 Domains, Excitations, and Spin-Glass-Like Behaviors |
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161 | (18) |
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5.1 Domain Structure Dynamics at Low Temperature |
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161 | (4) |
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5.2 The Phase Diagram of Anisotropic Antiferromagnets Above the Magnetic Percolation Threshold Concentration |
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165 | (8) |
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5.3 Excitations Near the Magnetic Percolation Threshold Concentration |
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173 | (6) |
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5.3.1 Fracton excitations in isotropic diluted d = 2 and d = 3 antiferromagnets near the magnetic percolation threshold concentration |
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174 | (2) |
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5.3.2 Excitations in anisotropic d = 2 and d = 3 diluted antiferromagnets near the magnetic percolation threshold concentration |
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176 | (3) |
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6 Experiments on Pure Magnets with Frustration |
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179 | (14) |
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6.1 The XY Stacked Triangular Lattice |
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180 | (4) |
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6.2 Examples of Other Chiral Systems |
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184 | (2) |
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184 | (2) |
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186 | (1) |
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6.3 Ising Stacked Triangular Lattice |
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186 | (7) |
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7 The Unusual Magnetism of LaCoOa: A Thermally Excited Exchange Interaction and Ordering at Twin Interfaces |
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193 | (6) |
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8 Conclusions and Outstanding Questions |
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199 | (8) |
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8.1 Overall Summary of the Results of the Experiments |
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199 | (3) |
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8.2 Some Open Questions About Equilibrium in the Random-Field Ising Model |
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202 | (3) |
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205 | (2) |
Bibliography |
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207 | (20) |
Index |
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227 | |