Spontaneous Radiative Decay of a Continuum
An interesting aspect of atoms capable of undergoing photoionization1 is the spontaneous decay of the excited continuum to a lower discrete state. This process is an extension of the classical spontaneous decay of a single two-level atom where the excited level is replaced by a continuum of states with a given dipole-strength distribution and initial mode of preparation. As is shown below,2 there exists a closed form for the time-dependent density matrix, which yields in the proper limit the spontaneous decay of an N-level atom where the only couplings are between the excited states and a common lowest state. In the trivial limit of a two-level atom we recover the well known expression for the Einstein A-coefficient.
Unable to display preview. Download preview PDF.
- 1.P. Lambropoulos and P. Zoller, Phys. Rev. A 24, 379 (1981); K.Google Scholar
- Rzazewski and J. H. Eberly, Phys. Rev. Lett. 47, 408 (1981), Phys. Rev. A 27, 2026 (1983); “Nato Advanced Study Institute on Quantum Electrodynamics and Quantum Optics,” Boulder, CO, 1983.Google Scholar
- 2.D. Agassi, submitted for publication.Google Scholar
- 3.G. S. Agarwal and D. Agassi, Phys. Rev. A 27, 2254 (1982); M. Lewenstein, J. W. Haus, and K. Rzazewski, Phys. Rev. Lett. 50, 417 (1983), and preprint, 1983; G. S. Agarwal, S. L. Haan, K. Burnett, and J. Cooper, Phys. Rev. A 26, 2277 (1982).Google Scholar
- 4.L. Allen and J. H. Eberly, “Optical Resonance and Two-Level Atoms,” John Wiley and Sons, New York, 1975.Google Scholar