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arXiv · 1912.10660

Back-action evading measurement of the collective mode of a Bose-Einstein condensate

M. Fani·A. Dalafi
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Abstract

In this paper, we investigate theoretically the back-action evading measurement of the collective mode of an interacting atomic Bose-Einstein condensate (BEC) trapped in an optical cavity which is driven coherently by a pump laser with a modulated amplitude. It is shown that for a specified kind of amplitude modulation of the driving laser, one can measure a generalized quadrature of the collective mode of the BEC indirectly through the output cavity field with a negligible backaction noise in the good-cavity limit. Nevertheless, the on-resonance added noise of measurement is suppressed below the standard quantum limit (SQL) even in the bad cavity limit. Moreover, the measurement precision can be controlled through the s-wave scattering frequency of atomic collisions.

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M. Fani, A. Dalafi. 2019-12-23. Back-action evading measurement of the collective mode of a Bose-Einstein condensate. https://doi.org/10.1364/josab.386227

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