Reversible decoherence of a mesoscopic superposition of field states

We describe the blueprint of an experiment in which the decoherence of a mesoscopic superposition of radiation states (''Schrodinger cat'') becomes a reversible process. When the high Q cavity containing the Schrodinger cat is coupled to another resonator, the mesoscopic quantum coherence first decays rapidly, then exhibits sharp revivals with the period of the energy exchange between the two cavities. The interpretation of this experiment emphasizes the link between decoherence and complementarity and leads to an illuminating quantitative interpretation of the usual irreversible decoherence phenomenon.