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Two-mode heterodyne phase detection

G. M. D'Ariano·M. F. Sacchi
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Abstract

We present an experimental scheme that achieves ideal phase detection on a two-mode field. The two modes $a$ and $b$ are the signal and image band modes of an heterodyne detector, with the field approaching an eigenstate of the photocurrent $\hat{Z}=a+b^†$. The field is obtained by means of a high-gain phase-insensitive amplifier followed by a high-transmissivity beam-splitter with a strong local oscillator at the frequency of one of the two modes.

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G. M. D'Ariano, M. F. Sacchi. 2001-09-27. Two-mode heterodyne phase detection. https://doi.org/10.1103/physreva.52.r4309

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