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arXiv · 1510.09062

Measurement of the squeezed vacuum state by a bichromatic local oscillator

Wei Li·Xudong Yu·Jing Zhang
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Abstract

We present the experimental measurement of a squeezed vacuum state by means of a bichromatic local oscillator (BLO). A pair of local oscillators at $\pm$5 MHz around the central frequency $\omega_{0}$ of the fundamental field with equal power are generated by three acousto-optic modulators and phase-locked, which are used as a BLO. The squeezed vacuum light are detected by a phase-sensitive balanced-homodyne detection with a BLO. The baseband signal around $\omega_{0}$ combined with a broad squeezed field can be detected with the sensitivity below the shot-noise limit, in which the baseband signal is shifted to the vicinity of 5 MHz (the half of the BLO separation). This work has the important applications in quantum state measurement and quantum information

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Wei Li, Xudong Yu, Jing Zhang. 2015-10-30. Measurement of the squeezed vacuum state by a bichromatic local oscillator. https://doi.org/10.1364/ol.40.005299

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