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1 | (12) |
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1.1 Magnetism in Nanoparticles |
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1 | (3) |
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1.2 Characterization of Magnetic Nanoparticles |
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4 | (2) |
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1.3 What We Cover in This Thesis |
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6 | (3) |
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9 | (4) |
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10 | (3) |
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2 Experimental Techniques |
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13 | (18) |
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2.1 Transmission Electron Microscopy |
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13 | (2) |
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14 | (1) |
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2.1.2 FEI Tecnai™ G2 F30 STWIN |
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15 | (1) |
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2.2 SQUID Based Magnetometry |
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15 | (2) |
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2.3 Anomalous Hall Effect |
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17 | (1) |
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2.4 X-ray Absorption Spectroscopies in Synchrotron Radiation Facilities |
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18 | (13) |
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2.4.1 X-ray Absorption Fine Structure |
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21 | (4) |
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2.4.2 X-ray Magnetic Circular Dichroism |
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25 | (4) |
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29 | (2) |
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3 Structural and Magnetic Properties of Amorphous Co--W Alloyed Nanoparticles |
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31 | (36) |
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32 | (2) |
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3.2 Morphological and Structural Study |
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34 | (15) |
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3.2.1 Microscopy Measurements |
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34 | (5) |
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3.2.2 XANES and EXAFS Measurements |
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39 | (10) |
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49 | (10) |
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3.3.1 SQUID-Based Magnetometry |
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49 | (6) |
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3.3.2 Magnetic Anisotropy of the Co---W Particles |
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55 | (1) |
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3.3.3 X-ray Magnetic Circular Dichroism Magnetometry |
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56 | (3) |
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59 | (5) |
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64 | (3) |
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64 | (3) |
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4 Breakdown of Hund's Third Rule in Amorphous Co---W Alloy Nanoparticles |
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67 | (16) |
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4.1 XANES and XMCD Measurements |
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68 | (6) |
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69 | (2) |
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4.1.2 W L2,3 Edges Results |
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71 | (3) |
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4.2 Calculations of DOS, XANES and XMCD |
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74 | (4) |
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75 | (1) |
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76 | (1) |
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77 | (1) |
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78 | (2) |
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80 | (3) |
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80 | (3) |
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5 Structural and Magnetic Properties of Co---Pt Nanoparticles |
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83 | (32) |
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84 | (1) |
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5.2 Morphological and Structural Study |
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84 | (9) |
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5.2.1 Microscopy Measurements |
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84 | (2) |
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5.2.2 XANES and EXAFS Measurements |
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86 | (7) |
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93 | (15) |
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5.3.1 SQUID-Based Magnetometry |
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93 | (6) |
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5.3.2 Anomalous Hall Effect Magnetometry |
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99 | (2) |
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5.3.3 X-ray Magnetic Circular Dichroism Magnetometry |
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101 | (7) |
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108 | (3) |
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111 | (4) |
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112 | (3) |
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6 d-Band Magnetism of Ag, Au, Pd and Pt Nanostructured Materials |
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115 | (12) |
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6.1 Magnetism in Bulk Metals |
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115 | (2) |
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6.2 Induced Magnetism in Nanoparticle Matrix |
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117 | (1) |
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6.3 Intrinsic Magnetic Moment in M Nanoparticles |
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118 | (5) |
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123 | (4) |
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124 | (3) |
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7 Transverse Susceptibility Measurement System for the PPMS |
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127 | (18) |
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7.1 Theoretical Model of the Magnetic Transverse Susceptibility |
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128 | (2) |
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7.2 Description of the TS Measurement System |
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130 | (2) |
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7.3 Design and Implementation of the Oscillator Circuit |
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132 | (5) |
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137 | (1) |
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137 | (5) |
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7.5.1 Test Measurements on an Empty Coil |
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137 | (2) |
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7.5.2 Calibration of the TS Measurement System with Gd2O3 |
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139 | (1) |
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7.5.3 Test Measurements on a Known and Previously Characterized Sample with a TDO Based TS System |
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140 | (2) |
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7.5.4 Low Temperature Measurements on TmCo2 |
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142 | (1) |
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142 | (3) |
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143 | (2) |
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8 Transverse Susceptibility of Iron Oxide Nanoparticles Systems |
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145 | (18) |
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8.1 Magnetite Nanoparticles |
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145 | (9) |
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146 | (2) |
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8.1.2 Magnetic Properties |
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148 | (2) |
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150 | (3) |
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153 | (1) |
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8.2 Maghemite Nanoparticles |
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154 | (9) |
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155 | (1) |
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156 | (3) |
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159 | (1) |
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160 | (3) |
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163 | |
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164 | |
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165 | |