Oxford University Press eBooks

Coherent interaction of light with atoms

J. C. Garrison, R. Y. Chiao

Published Jun 5, 2008• 0 citations

Abstract

The perturbation expansion (Chapter 4) fails if the incident field — assumed to be resonant with an atomic transition — has a coherence time that is long compared to the spontaneous emission time. The dominance of resonance effects is used to replace the perturbation expansion by the resonant-wave approximation, which approximately describes the joint evolution of the field-atom system for long times. This approach is employed to describe quantum propagation of spontaneously emitted photons. When combined with the Markov approximation, it yields the Weisskopf-Wigner model for single-photon emission and two-photon cascade emission. The chapter ends with a discussion of the semi-classical limit, Rabi oscillations, the Bloch equation, and adiabatic elimination.

DOI: 10.1093/acprof:oso/9780198508861.003.0012

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