Rabi Oscillations Revival Induced by Time Reversal: A Test of Mesoscopic Quantum Coherence

Collège de France, Lutetia Parisorum, Île-de-France, France
Physical Review Letters (Impact Factor: 7.51). 02/2005; 94(1):010401. DOI: 10.1103/PhysRevLett.94.010401
Source: PubMed


Using an echo technique proposed by Morigi et al. [Phys. Rev. A 65, 040102 (2002)], we have time-reversed the atom-field interaction in a cavity quantum electrodynamics experiment. The collapse of the atomic Rabi oscillation in a coherent field is reversed, resulting in an induced revival signal. The amplitude of this "echo" is sensitive to nonunitary decoherence processes. Its observation demonstrates the existence of a mesoscopic quantum superposition of field states in the cavity between the collapse and the revival times.

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Available from: A. Auffèves, May 12, 2014
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    • "This feature only disappears in the mathematical limit of strictly infinite volume as is implicitly assumed in [8]. In fact, revivals have been confirmed experimentally in various setups and also in the context of light-matter interactions [13]. Various decoherence models all differ in terms of interactions and physical conditions, which results in different parameter and functional dependence of decoherence. "
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