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Quantum Feedback for Protection of Schroedinger-cat states

Mauro Fortunato·Paolo Tombesi·David Vitali·Jean-Michel Raimond
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Abstract

We review the use of quantum feedback for combatting the decoherence of Schroedinger-cat-like states in electromagnetic cavities, with special emphasys on our recent proposal of an automatic mechanism based on the injection of appropriately prepared ``probe'' and ``feedback'' Rydberg atoms. In the latter scheme, the information transmission from the probe to the feedback atom is directly mediated by a second auxiliary cavity. The detection efficiency for the probe atom is no longer a critical parameter, and the decoherence time of the linear superposition state can be significantly increased using presently available technology.

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Mauro Fortunato, Paolo Tombesi, David Vitali, Jean-Michel Raimond. 2000-04-06. Quantum Feedback for Protection of Schroedinger-cat states. https://doi.org/10.1142/9789812793560_0014

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