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Limit to non-destructive optical detection of atoms

J. J. Hope·J. D. Close
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Abstract

All optical techniques used to probe the properties of Bose-Einstein condensates have been based on dispersion and absorption that can be described by a two-level atom. Both phenomena lead to spontaneous emission that is destructive. Recently, both were shown to lead to the same limit to the signal to noise ratio for a given destruction. We generalise this result to show that no single-pass optical technique using classical light, based on any number of lasers or coherences between any number of levels, can exceed the limit imposed by the two-level atom. This puts significant restrictions on potential non-destructive measurement schemes.

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J. J. Hope, J. D. Close. 2003-08-28. Limit to non-destructive optical detection of atoms. https://doi.org/10.1103/physrevlett.93.180402

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