1. Introduction 2. Review of Classical Electrodynamics 3. Review of Quantum Mechanics 4. The Spontaneous Emission of Radiation 5. Selection Rules for Electric Dipole Transitions 6. Measurement of Radiative Lifetimes of Atoms and Molecules 7. Forbidden Transitions and Metastable Atoms 8. The Width and Shape of Spectral Lines 9. The Absorption and Stimulated Emission of Radiation 10. Radiative Transfer and the Formation of Spectral Lines 11. Population Inversion Mechanisms in Gas Lasers 12. Resonant Modes of Optical Cavities 13. Saturation Characteristics and the Single-Frequency Operation of Gas Lasers 14. Turnable Dye Lasers and Atomic Spectroscopy 15. The Hanle Effect and the Theory of Resonance Flourescence Experiments 16. Optical Double Resonance Experiments 17. Optical Pumping Experiments 18. The Hyperfine Structure of Atoms and its Investigation by Magnetic Resonance Methods Appendix
Introduction 2. Review of Classical Electrodynamics 3. Review of Quantum Mechanics 4. The Spontaneous Emission of Radiation 5. Selection Rules for Electric Dipole Transitions 6. Measurement of Radiative Lifetimes of Atoms and Molecules 7. Forbidden Transitions and Metastable Atoms 8. The Width and Shape of Spectral Lines 9. The Absorption and Stimulated Emission of Radiation 10. Radiative Transfer and the Formation of Spectral Lines 11. Population Inversion Mechanisms in Gas Lasers 12. Resonant Modes of Optical Cavities 13. Saturation Characteristics and the Single-Frequency Operation of Gas Lasers 14. Turnable Dye Lasers and Atomic Spectroscopy 15. The Hanle Effect and the Theory of Resonance Flourescence Experiments 16. Optical Double Resonance Experiments 17. Optical Pumping Experiments 18. The Hyperfine Structure of Atoms and its Investigation by Magnetic Resonance Methods Appendix
An advanced undergraduate experiment to study the 5P3/2→6P3/2 electric quadrupole transition in rubidium atoms is presented. The experiment uses two external cavity diode lasers, one operating at the D2 rubidium resonance line and the other built with commercial parts to emit at 911 nm. The lasers produce the 5s→5p→6p excitation sequence in which the second step is the forbidden transition. Production of atoms in the 6P3/2 state is observed by detection of the 420 nm fluorescence that results from electric dipole decay into the ground state. Lines whose widths are significantly narrower than the Doppler width are used to study the hyperfine structure of the 6P3/2 state in rubidium. The spectra illustrate characteristics unique to electric dipole forbidden transitions, like the electric quadrupole selection rules; they are also used to show general aspects of two-color laser spectroscopy such as velocity selection and hyperfine pumping.
PART I: INTRODUCTION AND BACKGROUND 1. Introduction 2. Classical optics 3. Quantum mechanics 4. Radiative transitions in atoms PART II: PHOTONS 5. Photon statistics 6. Photon antibunching 7. Coherent states and squeezed light 8. Photon number states PART III: ATOM-PHOTON INTERACTIONS 9. Resonant light-atom interactions 10. Atoms in cavities 11. Cold atoms PART IV: QUANTUM INFORMATION PROCESSING 12. Quantum cryptography 13. Quantum computing 14. Entangled states and quantum teleportation APPENDICES A. Poisson statistics B. Parametric amplification C. The density of states D. Low dimensional semiconductor structures E. Nuclear magnetic resonance F. Bose-Einstein condensation
The ground electronic state of even such simple atoms as those of alkali elements has the set of sublevels. These sublevels are hyperfine (HF) components and magnetic sublevels. The collisions with particles of nonmagnetic buffer gas or even with walls (when walls have proper coating) do not mix practically the populations of ground state HF sublevels, if the orbital moment of electrons in the ground state is equal to zero. Due to this reason these sublevels may be extremely long lived. Because of this, for instance, the so-called effects of optical orientation and optical pumping are apparent in atoms of alkali metals. The radiation can pump practically all the atoms (with which there is effective interaction) to a single HF component. In a situation in which optical pumping is a minor effect, the monochromatic absorption line consists of separate lines corresponding to intra-atomic transitions. The optical pumping is not significant, for example, if the radiation intensity is so low that now pumping between HF sublevels occurs in the time it takes the atom to traverse the light beam. Under the conditions of optical pumping and when other nonlinear effects are present, the absorption line profile can undergo considerable alteration. Many theoretical and experimental investigations have been done in the laser spectroscopy of resonant transitions of atoms (atoms of alkali metals) under the conditions of optical pumping within ground state HF structure. A characteristic feature of all such investigations is the velocity-selective excitation of absorbing atoms. Also, as a rule, the value of HF splitting is not very big in comparison to Doppler broadening in these experiments. Under such conditions, the absorption spectra consists of Doppler- broadened lines with nonlinear resonances, which emerge when two fields of different frequencies or different propagation directions are employed. When only one monochromatic traveling wave is employed, optical pumping leads to formation of a single smooth absorption line occupying a position between the resonant transitions frequencies associated with HF components. As HF splitting grows, the line profile remains smooth, its width is approximately equal to the size of the HF splitting. The strength of the optical pumping from one ground state HF component to another is greater for greater HF splitting in comparison to the Doppler width. In this regard, Cs and Rb are the most typical of the alkali atoms (the HF splitting exceeds the Doppler width by a factor close to 20). This is the qualitative picture of the absorption line profile (particularly for a monochromatic radiation) under the conditions of optical pumping between the HF sublevels of the electronic ground state, this qualitative picture had formed by now.
I. RELATIVITY. 1. The Space and Time of Relativity. 2. Relativistic Mechanics. II. QUANTUM MECHANICS. 3. Atoms. 4. Quantization of Light. 5. Quantization of Atomic Energy Levels. 6. Matter Waves. 7. The Schrodinger Equation in One Dimension. 8. The Three-Dimensional Schrodinger Equation. 9. Electron Spin. 10. Multielectron Atoms the Pauli Principle and the Periodic Table. 11. Atomic Transitions and Radiation. III. SYSTEMS WITH TWO OR MORE ATOMS. 12. Molecules. 13. Solids - Theory. 14. Solids - Applications. 15. Statistical Mechanics. IV. SUBATOMIC PHYSICS. 16. The Structure of Atomic Nuclei. 17. Radioactivity and Nuclear Reactions. 18. Elementary Particles. APPENDIXES. A. Physical Constants. B. Useful Mathematical Relations. C. Alphabetical List of the Elements. D. Atomic and Nuclear Data. Suggestions for Further Reading. Picture Credits and References. Answers to Odd-Numbered Problems. Index.
This concise and accessible book provides a detailed introduction to the fundamental principles of atomic physics at an undergraduate level. Concepts are explained in an intuitive way and the book assumes only a basic knowledge of quantum mechanics and electromagnetism. With a compact format specifically designed for students, the first part of the book covers the key principles of the subject, including the quantum theory of the hydrogen atom, radiative transitions, the shell model of multi-electron atoms, spin-orbit coupling, and the effects of external fields. The second part provides an introduction to the four key applications of atomic physics: lasers, cold atoms, solid-state spectroscopy and astrophysics. This highly pedagogical text includes worked examples and end of chapter problems to allow students to test their knowledge, as well as numerous diagrams of key concepts, making it perfect for undergraduate students looking for a succinct primer on the concepts and applications of atomic physics.
Laser Generation without Population Inversion in the Red Wing of the D1-Line of Alkali Metal Atoms under Resonant Diode Pumping
A new method of laser radiation generation without population inversion in the red wing of the D1 -line of alkali metal atoms under resonant absorption of broadband radiation of pump laser diodes at the D1 transition is studied theoretically. The appearance of laser generation is caused by the fact that the probability of stimulated emission in the red wing of the spectral line exceeds the probability of absorption if homogeneous broadening due to interaction between active particles and the buffer gas significantly exceeds the natural broadening (under high pressures of the buffer gas). Analytical formulas representing the operation of a transversely diode-pumped alkali metal vapor laser are obtained. It is found that cesium atoms are the most promising object for observation of laser generation without population inversion in the red wing of the D1 -line of alkali metal atoms. In a sufficiently long active medium (the length of the medium is 50 times its width), the efficiency of pumping radiation conversion into laser radiation can reach 57% at a buffer gas pressure of 5 atm, a pump diode radiation intensity of 5 kW/cm 2 , and a half-width of its spectrum of 1 cm −1 . The laser radiation frequency can be tuned by several tens of cm −1 .