Paradoxical evolution of the number of photons in the Jaynes-Cummings model

摘要

I report a paradoxical result in the resonant Jaynes-Cummings model, in which atomic excitation by photon absorption is accompanied by an increase of the number of photons. I show that this always holds in the short-time regime for initial fields with super-Poissonian photon statistics. I provide a purely dynamical explanation of the effect that holds in both the quantum and the semiclassical regimes, and I discuss the relation of this counterintuitive photon behavior with the bunching effect.