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Chinese Physics Letters

Experimental Demonstration of a Displacement Measurement of an Optical Beam beyond the Quantum Noise Limit

Hengxin Sun, Zunlong Liu, Kui Liu, Rongguo Yang, Junxiang Zhang, Jiangrui Gao

Published Aug 1, 2014• 15 citations
Publisher

Abstract

We experimentally generate a spatially squeezed light beam and realize a small-displacement measurement beyond the quantum noise limit with this squeezed light. Moreover, we measure about −2.2±0.2 dB spatial squeezing and reduce the minimum measurable displacement from 1.17 Å to 0.99 Å with the signal-to-noise ratio normalized to 1.
DOI
10.1088/0256-307x/31/8/084202

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