Article

Nondestructive Rydberg Atom Counting with Mesoscopic Fields in a Cavity

Collège de France, Lutetia Parisorum, Île-de-France, France
Physical Review Letters (Impact Factor: 7.51). 04/2005; 94(11):113601. DOI: 10.1103/PhysRevLett.94.113601
Source: PubMed

ABSTRACT We present an efficient, state-selective, nondemolition atom-counting procedure based on the dispersive interaction of a sample of circular Rydberg atoms with a mesoscopic field contained in a high-quality superconducting cavity. The state-dependent atomic index of refraction, proportional to the atom number, shifts the classical field phase. A homodyne procedure translates the information from the phase to the intensity. The final field intensity is readout by a mesoscopic atomic sample. This method opens promising routes for quantum information processing and nonclassical state generation with Rydberg atoms.

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