The modern electron microscope, as a result of recent revolutionary developments and many evolutionary ones, now yields a wealth of quantitative knowledge pertaining to structure, dynamics, and function barely matched by any other single scientific instrument. It is also poised to contribute much new spatially-resolved and time-resolved insights of central importance in the exploration of most aspects of condensed matter, ranging from the physical to the biological sciences. Whereas in all conventional EM methods, imaging, diffraction, and chemical analyses have been conducted in a static - time-integrated - manner, now it has become possible to unite the time domain with the spatial one, thereby creating four-dimensional (4D) electron microscopy. This advance is based on the fundamental concept of timed, coherent single-electron packets, or electron pulses, which are liberated with femtosecond durations. Structural phase transitions, mechanical deformations, and the embryonic stages of melting and crystallization are examples of phenomena that can now be imaged in unprecedented structural detail with high spatial resolution, and ten orders of magnitude as fast as hitherto. No monograph in existence attempts to cover the revolutionary dimensions that EM in its various modes of operation nowadays makes possible. The authors of this book chart these developments, and also compare the merits of coherent electron waves with those of synchrotron radiation. They judge it prudent to recall some important basic procedural and theoretical aspects of imaging and diffraction so that the reader may better comprehend the significance of the new vistas and applications now afoot. This book is not a vade mecum - numerous other texts are available for the practitioner for that purpose. It is instead an in-depth expose of the paradigm concepts and the developed techniques that can now be executed to gain new knowledge in the entire domain of biological and physical science, and in the four dimensions of space and time.
Author(s): Ahmed H. Zewail, John M. Thomas
Publisher: Imperial College Press
Year: 2009
Language: English
Pages: 359
Tags: Физика;Практикумы, экспериментальная физика и физические методы исследования;
Acknowledgements......Page 6
Preface......Page 8
Contents......Page 10
1. Historical Perspectives: From Camera Obscura to 4D Imaging......Page 14
References......Page 26
2.1 Coherence — A Simplified Prelude......Page 28
2.2 Optical Coherence and Decoherence......Page 31
2.3.1 Rayleigh criterion and resolution......Page 35
2.3.2 Diffraction from atoms and molecules......Page 40
2.4 Coherence and Diffraction in Crystallography......Page 42
2.5.1 Basic concepts......Page 47
2.5.2 Coherence of the source, lateral and temporal......Page 53
2.5.3 Imaging in electron microscopy......Page 55
2.6 Instrumental Factors Limiting Coherence......Page 61
References......Page 63
3. From 2D to 3D Structural Imaging: Salient Concepts......Page 66
3.1 2D and 3D Imaging......Page 68
3.2 Electron Crystallography: Combining Diffraction and Imaging......Page 74
3.3 High-Resolution Scanning Transmission Electron Microscopy......Page 76
3.3.1 Use of STEM for electron tomography of inorganic materials......Page 80
3.4 Biological and Other Organic Materials......Page 82
3.4.1 Macromolecular architecture visualized by cryo-electron tomography......Page 83
3.5 Electron-Energy-Loss Spectroscopy and Imaging by Energy-Filtered TEM......Page 86
3.5.1 Combined EELS and ET in cellular biology......Page 88
3.6 Electron Holography......Page 90
References......Page 92
4.2.1 Encapsulated nanocrystalline structures......Page 96
4.2.2 Nanocrystalline catalyst particles of platinum......Page 97
4.2.3 Microporous catalysts and molecular sieves......Page 99
4.2.4 Other zeolite structures......Page 101
4.2.5 Structures of complex catalytic oxides solved by HRSTEM......Page 102
4.2.6 The value of electron diffraction in solving 3D structures......Page 105
4.3 Electron Tomography......Page 107
4.4 Electron Holography......Page 108
4.5 Electron Crystallography......Page 113
4.5.1 Other complex inorganic structures......Page 114
4.5.2 Complex biological structures......Page 116
4.6 Electron-Energy-Loss Spectroscopy and Imaging......Page 120
4.7 Atomic Resolution in an Environmental TEM......Page 124
4.7.1 Atomic-scale electron microscopy at ambient pressure by exploiting the technology of microelectromechanical systems......Page 129
References......Page 131
5.1.1 Matter particle–wave duality......Page 136
5.1.2 Analogy with light......Page 139
5.1.3 Classical atoms: Wave packets......Page 140
5.1.4 Paradigm case study: Two atoms......Page 143
5.2.1 High-speed shutters......Page 147
5.2.2 Stroboscopy......Page 151
5.2.3 Ultrafast techniques......Page 152
5.2.4 Ultrafast lasers......Page 156
5.3.1 Coherence of ultrafast packets......Page 160
5.3.2 The double-slit experiment revisited......Page 165
5.3.3 Ultrafast versus fast imaging......Page 167
5.3.4 The velocity mismatch and attosecond regime......Page 170
5.4 4D Microscopy: Brightness, Coherence and Degeneracy......Page 175
5.4.1 Coherence volume and degeneracy......Page 177
5.4.2 Brightness and degeneracy......Page 181
5.4.3 Coherence and Contrast......Page 185
5.4.4 Contrast, dose, and resolution......Page 187
References......Page 189
6.1 Developments at Caltech — A Brief History......Page 192
6.2 Instruments and Techniques......Page 194
6.3.1 Selected-area image (diffraction) dynamics......Page 208
6.3.2 Dynamical morphology: Time-dependent warping......Page 209
6.3.3 Proof of principle: Gold dynamics......Page 212
6.3.4.1 Atomic motions......Page 217
6.3.4.2 Coherent resonances in diffraction: Longitudinal Young’s modulus......Page 221
6.3.4.3 Resonances in images: Longitudinal elasticity......Page 224
6.3.4.4 Emergence of mechanical drumming: Transverse ellasticity......Page 226
6.3.4.5 Moiré fringe dynamics......Page 229
6.3.4.6 FEELS: Femtosecond EELS and chemical bonding......Page 231
6.4 Selected Other Applications......Page 234
6.4.1.1 Metal–insulator transformation......Page 236
6.4.1.2 Transient phases of superconducting cuprates......Page 240
6.4.2 Nucleation and crystallization phenomena......Page 243
6.4.3.1 Water on hydrophobic and hydrophilic substrates......Page 247
6.4.3.2 Bilayers, phospholipids, and cells......Page 250
6.4.4.1 Channel gating......Page 255
6.4.4.2 Functional cantilevers......Page 258
6.4.4.3 Optoelectronic nanorods......Page 262
6.4.4.4 Diffraction and materials surface charging......Page 266
6.5 4D Convergent Beam UEM: Nanodiffraction......Page 269
6.6 4D Near-Field UEM: Nanostructures and Plasmonics......Page 276
References......Page 282
7.1 Introduction......Page 288
7.2 Transmission X-ray Microscopy and X-ray Microscopic Tomography......Page 290
7.2.1 X-ray tomography of biological cells......Page 294
7.3 Coherent X-ray Diffraction Imaging......Page 296
7.4 Extraction of Structures from Powdered Specimens......Page 300
7.4.2 Energy-dispersive X-ray diffraction......Page 301
7.4.3 X-ray absorption fine structure spectroscopy......Page 303
7.4.4 Combined X-ray absorption and X-ray diffraction for in situ studies of powdered catalysts......Page 306
7.5 Studies of Species in Solution......Page 307
7.6 Laue Crystallography: Static and Dynamic......Page 310
7.7 The Perennial Problem of Radiation Damage......Page 312
7.8 Summarizing Assessment......Page 314
References......Page 315
8.1 Visualization and Complexity......Page 322
8.2 Complexity Paradox: Coherence and Creative Chaos......Page 327
8.3 From 2(3)D to 4D Microscopy......Page 329
8.4.1 Materials science......Page 334
8.4.2 Biological UEM......Page 336
8.4.3 Structural dynamics: Theory and experiment......Page 337
8.4.4 Aligned- and single-molecule imaging......Page 343
8.4.5 Imaging with attosecond electrons......Page 346
References......Page 350
Biographical Profiles......Page 356
