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

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Collège de France, Lutetia Parisorum, Île-de-France, France
(Impact Factor: 7.73). 02/2005; 94(1):010401. DOI: 10.1103/PhysRevLett.94.010401
Source: PubMed

ABSTRACT 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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