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arXiv · 1712.01553

Quantum enhanced joint measurement of multiple non-commuting observables with SU(1,1) interferometer

Yuhong Liu·Jiamin Li·Liang Cui·Nan Huo·Syed M Assad·Xiaoying Li·Z. Y. Ou
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Abstract

Heisenberg uncertainty relation in quantum mechanics sets the limit on the measurement precision of non-commuting observables, which prevents us from measuring them accurately at the same time. In some applications, however, the information are embedded in two or more non-commuting observables. On the other hand, quantum entanglement allows us to infer through Einstein-Podolsky-Rosen correlations two conjugate observables with precision better than what is allowed by Heisenberg uncertainty relation. With the help of the newly developed SU(1,1) interferometer, we implement a scheme to measure jointly information encoded in multiple non-commuting observables of an optical field with a signal-to-noise ratio improvement of about 20 % over the standard quantum limit on all measured quantities simultaneously. This scheme can be generalized to the joint measurement of information in arbitrary number of non-commuting observables.

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Yuhong Liu, Jiamin Li, Liang Cui, Nan Huo, Syed M Assad, Xiaoying Li, Z. Y. Ou. 2017-12-14. Quantum enhanced joint measurement of multiple non-commuting observables with SU(1,1) interferometer. https://doi.org/10.1364/oe.26.027705

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