Cavity Quantum Electrodynamics

Abstract

The dynamics of a small system coupled to a large reservoir can be described using several different formalisms developed in the previous chapter and illustrated with the system of a two-level atom in the open radiation field. Here we adapt this general theory to a system represented by a single-mode cavity field coupled to a reservoir of harmonic oscillators. We first derive the master equation, the Fokker-Planck equation and the Heisenberg-Langevin equations of motion for the cavity field. We then discuss certain aspects of cavity quantum electrodynamics (QED) which studies the behavior of an atom interacting with the cavity field. In particular, we consider a two-level atom in a leaky cavity and show that, depending on the parameters of the cavity, the atom-cavity system can exhibit damped Rabi oscillations, or the optical cavity can modify the rate of atomic spontaneous emission. Finally, we demonstrate that by employing the STIRAP techniques with a three-level atom confined in a leaky cavity, one can realize a deterministic source of single-photons. Other aspects of cavity QED will be discussed in Chap. 10 in the context of physical implementations of quantum information processing.