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Motional Squashed States

Stefano Mancini·David Vitali·Paolo Tombesi
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Abstract

We show that by using a feedback loop it is possible to reduce the fluctuations in one quadrature of the vibrational degree of freedom of a trapped ion below the quantum limit. The stationary state is not a proper squeezed state, but rather a ``squashed'' state, since the uncertainty in the orthogonal quadrature, which is larger than the standard quantum limit, is unaffected by the feedback action.

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Stefano Mancini, David Vitali, Paolo Tombesi. 1999-11-15. Motional Squashed States. https://doi.org/10.1088/1464-4266/2/2/322

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