QUANTUM JUMPS

This chapter describes the quantum jumps. The concept of quantum jumps began with the theory of atomic structure. According to this theory, an atom at rest can exist in any of a discrete set of energy levels, and the fundamental radiative processes proceed by abrupt jumps among these levels. The observation of quantum jumps requires a spectroscopic sample consisting of a single atom or a very few atoms. Only ions have been trapped as single isolated particles. Telegraphic fluorescence is the only effect that permits the observation of quantum jumps. The quantum formalism attributes electron shelving to the lack of fluorescence, whereas the intuitive picture of the process attributed the lack of fluorescence to electron shelving. The observation of photon anti-bunching in single-atom resonance fluorescence and other experiments provide evidence for the discrete nature of quantum transitions in individual quantum systems. © 1990, Elsevier B.V. All rights reserved.