Dynamics During Spectroscopic Transitions: Basic Concepts

ISBN-13: 9783642794094 / Angielski / Miękka / 2011 / 580 str.

Ernst Lippert; J. D. Macomber

Opis

"How does a photon get into an atom?" This question puzzled not only leading scientists, e.g. Schrodinger and Heisenberg. It is still asked by students. And it is, indeed, a key question of quantum mechanics.
James D. Macomber's book was the first to provide a didactic and unified approach to the answer. It has been updated with recent experimental results and modern theoretical interpretations, including quantum correlation effects in condensed matter, four-wave mixing and synchrotron radiation . The book has been written for final year undergraduate students in Chemistry and Physics. It provides an understanding for similarities among the spectroscopic methods, and is stimulating to read."

Spis treści

I. Well-known Principles.- 1 Introduction.- 1.1 Electric Fields in Atoms and Waves.- 1.2 Photoionization and Nonresonant Scattering.- 1.3 Resonant Interactions and Spectroscopy.- 1.4 The Bouguer-Lambert-Beer Law.- 1.5 The Importance of Spectroscopic Transitions.- 1.6 The Question of Dynamics.- 1.7 Early History of the Quantum Theory.- 1.8 Dynamics During Spectroscopic Transitions.- 1.9 References.- 1.10 Problems.- 2 Elementary Quantum Theory.- 2.1 States and Their Properties: Operators and Kets.- 2.2 Stationary States: Eigenkets and Eigenfunctions.- 2.3 Schrödinger’s Equation: Time Dependence of ?.- 2.4 Kets and Bras: Orthogonality and Normalization.- 2.5 Quantum Systems “in-between” Eigenstates.- 2.6 Eigenvalues and Expectation Values.- 2.7 Superposed Eigenfunctions and Perturbed Eigenfunctions.- 2.8 References.- 2.9 Problems.- 3 Elementary Electromagnetic Theory.- 3.1 Relationship Between Classical and Quantum-Mechanical Theories.- 3.2 Applicability of Classical and Quantum Theories.- 3.3 When the Classical Theory May Be Used.- 3.4 Waves and Particles and Their “Sizes”.- 3.5 Electromagnetic Waves and Quantum Systems: Size Ratios.- 3.6 Series Expansions for Electromagnetic Fields.- 3.7 Interactions Between Multipoles and Field Asymmetries.- 3.8 Electromagnetic Waves and Quantum Systems: Interactions.- 3.9 Complex Susceptibilities, Electric and Magnetic.- 3.10 Effect of Susceptibilities on Wave Propagation.- 3.11 Absorption Coefficient and Refractive Index.- 3.12 Phase Relationships: Absorption, Emission, and Dispersion.- 3.13 References.- 3.14 Problems.- 4 Interaction of Radiation and Matter.- 4.1 Dipoles and Waves: the Semiclassical Theory.- 4.2 The Transition Dipole Moment of a Hydrogen Atom.- 4.3 Conceptual Problems with the Theory.- 4.4 Quantum Jumps and the Uncertainty Principle.- 4.5 The Spin?½ System.- 4.6 A Geometrical Model of the Transition Process.- 4.7 Quantum Jumps on the Sphere of Certainty.- 4.8 Magnetic Resonance in Bulk and in Beams.- 4.9 The Stern-Gerlach Experiment.- 4.10 State Selection in Beam Experiments.- 4.11 The Rabi Magnetic Resonance Experiment.- 4.12 The Ramsey Separated Oscillating Fields Experiment.- 4.13 A Thought Experiment.- 4.14 Difficulties with the Proposed Experiment.- 4.15 The Bloom Transverse Stern-Gerlach Effect.- 4.16 Quantum Jumps and Superposition States: Conclusion.- 4.17 References.- 4.18 Problems.- II. Quantum Statistics.- 5 Ensembles of Radiating Systems.- 5.1 Reasons for the Use of Statistical Methods.- 5.2 Coherent and Incoherent Perturbations.- 5.3 Strongly Coupled and Weakly Coupled Systems.- 5.4 Computing Expectation Values from Superposition Coefficients.- 5.5 Equations of Motion for the Operator D.- 5.6 The Density Operator.- 5.7 Properties of the Density Matrix.- 5.8 Effect of Relaxation on the Density Matrix.- 5.9 Equations of Motion for the Density Matrix.- 5.10 Coherence in Ensembles of Quantum Radiators.- 5.11 Creating, Observing, and Destroying Coherence.- 5.12 References.- 5.13 Problems.- 6 Relaxation Processes and Coherent Dissipative Structures.- 6.1 Dissipative Systems.- 6.2 Entanglement and Interference Effects.- 6.3 The Ensemble for an Ideal System.- 6.4 The Density Matrix.- 6.5 Variational Principles and the Negentropy.- 6.6 The Extreme Case.- 6.7 Resonance Picture of Unstable States.- 6.8 Resonances and Dissipative Dynamics.- 6.9 The Coherent-Dissipative Ensemble.- 6.10 References.- 6.11 Problems.- 7 Applications of CSM Theory.- 7.1 Occurrence of Coherent-Dissipative Structures.- 7.2 Proton Transfer Processes in Water and Aqueous Solutions.- 7.3 The Development of ODLRO and the Phases of High-Temperature Superconductors.- 7.4 Fractional Statistics in the Quantum Hall Effect.- 7.4.1 The Fractional QHE.- 7.4.2 Quantum States.- 7.4.3 The Many-Body System.- 7.4.4 High Correlation.- 7.4.5 Wigner Solids.- 7.5 Spontaneous and Stimulated Emission of Radiation in Masers.- 7.5.1 Einstein Relation.- 7.5.2 Cyclotron Maser Concept.- 7.5.3 Liouville Formulation of CMC.- 7.5.4 Self-Organization.- 7.5.5 Connection with the Gainfunction.- 7.5.6 Conclusion.- 7.6 Final Conclusions.- 7.7 References.- 7.8 Problems.- III. Gyrating Dipole Moments.- 8 Basic Principles of Magnetic Resonance.- 8.1 Operators Representing Orbital Angular Momentum.- 8.2 Operators Representing Spin Angular Momentum.- 8.3 Eigenkets of Spin; Raising and Lowering Operators.- 8.4 Number of States, Normalization, and Eigenvalues.- 8.5 Spinning Particles in Nature.- 8.6 The Effect of a Static Magnetic Field.- 8.7 The Effect of an Oscillating Magnetic Field.- 8.8 The Density Matrix for Magnetic Resonance.- 8.9 The Ensemble-Averaged Magnetization.- 8.10 Solutions to the Bloch Equations.- 8.11 Absorption and Stimulated Emission: Free-Induction Decay.- 8.12 The Crossed-Coil Nuclear Magnetic Resonance Spectrometer.- 8.13 Steady-State Magnetization: Curie’s Law.- 8.14 Conventional Nuclear Magnetic Resonance Spectroscopy: Slow Passage.- 8.15 Equivalence of Transient and Steady-State Methods.- 8.16 Spin Echoes.- 8.17 References.- 8.18 Problems.- 9 Spin Dynamics and Radical Reactions.- Key to Symbols.- 9.1 Molecules in Doublet States.- 9.2 Singlet and Triplet States.- 9.3 Intersystem Crossing by Magnetic Interactions.- 9.4 Spin Dynamics of Radical Pairs in High Fields.- 9.5 Combining Spin Dynamics and Radical Pair Dynamics.- 9.6 Chemically Induced Nuclear Spin Polarizations.- 9.7 Chemically Induced Electron Spin Polarizations.- 9.8 Quantum Beats.- 9.9 References.- 9.10 Problems.- 10 Generalization of the Gyroscopic Model.- 10.1 The Gyroscopic Model of the Interaction Process.- 10.2 Electric-Dipole-Allowed Transitions.- 10.3 Relaxation and Its Effect on Line Widths.- 10.4 Phase Interruption and Pressure Broadening.- 10.5 Other Relaxation Processes in Gases and Solids.- 10.6 Optical Analogs to Magnetic Resonance Phenomena.- 10.7 Photon Echoes: Qualitative Discussion.- 10.8 Angle of Echo Propagation Using the Gyroscopic Model.- 10.9 Mathematical Analysis of ?/2, ? Echoes.- 10.10 Self-Induced Transparency: Qualitative Discussion.- 10.11 Other Coherent Transient Phenomena.- 10.12 References.- 10.13 Problems.- IV. Applications of LASER and SR Techniques.- 11 Stimulated Scattering: Third Order Processes.- 11.1 Coherent Material Excitation.- 11.2 Theoretical Background of Four Wave Mixing (FWM).- 11.2.1 Extension of the Applicability of the Raman FWM-Equations and the Method of Their Solution.- 11.2.2 FWM Under Steady State Conditions.- 11.2.3 FWM Under Stationary Conditions.- 11.2.4 The Notation of Nonlinear Susceptibility.- 11.3 Coherent Antistokes Raman Spectroscopy.- 11.3.1 Determination of Nonlinear Susceptibilities by CARS Line Shape Analysis.- 11.3.2 Application of Special Polarization Arrangements to Discriminate Between Different Contributions to the CARS Signal.- 11.3.3 Background Suppression by Suitably Chosen Field Polarizations.- 11.4 Nonlinear Polarization Spectroscopy.- 11.4.1 Pressure-Induced FWM Signals.- 11.5 Time-Resolved Techniques of FWM.- 11.5.1 Characteristic Experimental Results.- 11.5.2 Increased Spectral Resolution Applying Specially Designed Pulsed FWM Techniques.- 11.5.3 Photon Echoes of Polyatomic Molecules in Condensed Phases.- 11.6 Time-Resolved Measurements with Incoherent Laser Beams Bearing ps- and Sub-ps-Fluctuations.- 11.6.1 CSRS with Incoherent Laser Light.- 11.6.2 White-Detector Limit.- 11.6.3 Spectrally Resolved Detection.- 11.6.4 Some Experimental Results.- 11.7 Material Excitation by SRS for a Frequency Modulated Statistically Fluctuating Laser.- 11.8 The Description of Molecular Susceptibilities by Feynman Diagrams.- 11.8.1 Rules for Deriving the ?(n)-Expressions from the Diagrams.- 11.8.2 The General Form of the ?(3)-Susceptibility Expression.- 11.8.3 Term Selection Under Resonance Excitation.- 11.8.4 Determination of Molecular Polarizations by the Feynman Diagram Technique in the Case of Time Dependent Fields.- 11.9 References.- 11.10 Problems.- 12 Transient Grating Spectroscopy.- Key to Symbols.- 12.1 Transient Grating and Four-Wave Interaction.- 12.2 Grating Excitation Mechanisms.- 12.3 Diffraction at a Grating.- 12.4 Characteristics of the Transient Grating Technique.- 12.5 Depopulation and Orientation Processes.- 12.6 Electronic Energy Transfer and Charge Carrier Dynamics.- 12.7 Mass and Heat Diffusion.- 12.8 Propagation of Ultrasonic Waves and Structural Relaxation.- 12.9 References.- 12.10 Problems.- 13 Synchrotron Radiation and Free Electron Lasers.- 13.1 Introduction.- 13.2 Synchrotron Radiation.- 13.3 Undulator Radiation.- 13.4 Free Electron Lasers.- 13.5 Accelerators for Light Sources and Undulators.- 13.6 VUV Optical Components.- 13.7 VUV Monochromators.- 13.8 Techniques for VUV Measurements.- 13.9 Far Infrared Instrumentation.- 13.10 Two-Color Experiments.- 13.11 References.- 13.12 Problems.

O autorze

Among the key questions that lead to the development of quantum theory was the problem of understanding the interaction of light with matter. Modern time-resolved spectroscopy has contributed tremendously to current theoretical models. This book addresses final year undergraduates and graduate students in Chemistry and Physics.