Quantum optics and the discrete-space discrete-time Jaynes-Cummings model

The Jaynes-Cummings model of early quantum optics is examined from the point of view of a discrete-space discrete-time formulation of the electromagnetic field (the FDTD formulation) excited by an elementary quantum Hertzian dipole associated to a single edge of the discrete-space lattice. The quantum Hertz dipole is a natural 2-level atomic system, and the quantum dynamics of the electromagnetic field in the discrete space surrounding the dipole, described by functional integrals over field space, is essentially a stochastic (Monte-Carlo) algorithm for solving the FDTD equations by searching for the field distribution about which the field action Lagrangian functional S is stationary.