High Frequency Acoustics in Colloid-Based Meso- and Nanostructures by Spontaneous Brillouin Light Scattering (eBook)

Supervisor’s Foreword 8
Acknowledgments 9
1 Introduction 18
1.1…General Introduction 18
1.2…Aims and Motivation 23
1.3…Outline 24
References 24
2 Basics and Brillouin Light Scattering 26
2.1…Elastic Waves in Condensed Matter 26
2.1.1 Elasticity Theory Basics 26
2.1.2 Elastic Waves in Isotropic Media 31
2.1.3 Spherical Waves 32
2.2…Light Scattering Basics 33
2.3…Brillouin Light Scattering 37
2.3.1 BLS Basics 38
2.3.2 BLS Instrumentation 42
2.3.3 Vibrational Modes of Individual Particles 49
References 51
3 Methods 52
3.1…Vertical Lifting Deposition and Colloidal Crystals 52
3.2…Melt Compression 54
3.3…Polymer and Colloid Characterization Techniques 55
3.3.1 Photon Correlation Spectroscopy 55
3.3.2 Electron Microscopy 56
3.3.3 Differential Scanning Calorimetry 57
3.3.4 Density Gradient Column 57
3.3.5 Wide Angle X-ray Scattering 58
3.3.6 UV/VIS Spectroscopy 58
3.3.7 Gel Permeation Chromatography 59
3.4…Theoretical Calculations 60
3.4.1 Single-sphere Scattering Cross-section Calculations 61
3.4.2 The Plane Wave Method 62
3.4.3 The Multiple Scattering Method 64
3.4.4 The Finite Element Method 68
References 68
4 The Vibrations of Individual Colloids 70
4.1…Introduction 70
4.2…Elastic Vibrations in Homogeneous Polymer Colloids 72
4.2.1 The ‘music’ of the spheres 72
4.2.2 The Influence of the Neighbors: Mixtures 78
4.2.3 The Influence of the Rigidity: Copolymers 80
4.2.4 The Influence of the Wave Vector: Suspensions 86
4.3…Elastic Vibrations in Nanostructured Colloids 88
4.3.1 The Influence of the Temperature: PS--SiO2 Core--Shell Particles 88
4.3.2 The Influence of the Components: SiO2--PMMA Core--Shell Particles 94
4.4…Materials 101
4.4.1 Homogeneous Polymer Colloids 101
4.4.2 Homogeneous Silica Colloids 102
4.4.3 PS--SiO2 Core--Shell Particles 102
4.4.4 SiO2--PMMA Core--Shell Particles 103
References 103
5Phononic Behavior of Colloidal Systems 105
5.1 Introduction 105
5.1.1 The Phononic Band Diagram 107
5.1.2 The Effective Medium 110
5.1.3 Phononic Band Gaps 112
5.1.3.1 Normalization 115
5.2 Effective Medium Velocity in Defect Doped Opals 116
5.3 Band Gaps in Polymer Opals and Disordered Systems 120
5.3.1 The Influence of the Order in Colloidal Systems 120
5.3.2 The Influence of the Composition in Disordered ColloidalSystems 127
5.4 Band Gaps in SiO2 Colloidal Systems 129
5.4.1 Phononic Behavior of Silica Suspensions 130
5.4.2 Silica–Poly(ethyl acrylate) Films (PhoXonics) 133
5.5 Materials 136
5.5.1 Melt Compressed Silica–Poly(ethyl acrylate) Films 137
6 Smaller than Colloids: Characterization of Stable Organic Glass 139
6.1…Introduction 139
6.2…BLS Experiments on IMC 140
6.3…Materials and Methods 144
6.3.1 Stable Glass 144
6.3.2 BLS Measurements 145
References 145
7 Concluding Remarks 147
7.1…Conclusions 147
7.2…Outlook 149
References 150
8 Appendix: Scattering Geometry 151
8.1…Transmission Case 151
8.2…Reflection Case 152
Curriculum Vitae 155
Presentations in International Conferences 156
Index 158