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arXiv · 1607.07332

Improving the phase super-sensitivity of squeezing-assisted interferometers by squeeze factor unbalancing

Mathieu Manceau·Farid Khalili·Maria Chekhova
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Abstract

The sensitivity properties of an SU(1,1) interferometer made of two cascaded parametric amplifiers, as well as of an ordinary SU(2) interferometer preceded by a squeezer and followed by an anti-squeezer, are theoretically investigated. Several possible experimental configurations are considered, such as the absence or presence of a seed beam, direct or homodyne detection scheme. In all cases we formulate the optimal conditions to achieve phase super-sensitivity, meaning a sensitivity overcoming the shot-noise limit. We show that for a given gain of the first parametric amplifier, unbalancing the interferometer by increasing the gain of the second amplifier improves the interferometer properties. In particular, a broader super-sensitivity phase range and a better overall sensitivity can be achieved by gain unbalancing.

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Mathieu Manceau, Farid Khalili, Maria Chekhova. 2016-07-25. Improving the phase super-sensitivity of squeezing-assisted interferometers by squeeze factor unbalancing. https://doi.org/10.1088/1367-2630%2Faa53d1

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