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Contractive Schroedinger cat states for a free mass

Lorenza Viola·Roberto Onofrio
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Abstract

Contractive states for a free quantum particle were introduced by Yuen [Yuen H P 1983 Phys. Rev. Lett. 51, 719] in an attempt to evade the standard quantum limit for repeated position measurements. We show how appropriate families of two- and three component ``Schroedinger cat states'' are able to support non-trivial correlations between the position and momentum observables leading to contractive behavior. The existence of contractive Schroedinger cat states is suggestive of potential novel roles of non-classical states for precision measurement schemes.

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Lorenza Viola, Roberto Onofrio. 2003-03-06. Contractive Schroedinger cat states for a free mass. https://doi.org/10.1088/1367-2630%2F5%2F1%2F305

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