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arXiv · 1803.07735

Phase amplification in optical interferometry with weak measurement

Li Li·Yuan Li·You-Lang Zhang·Sixia Yu·Chao-Yang Lu·Nai-Le Liu·Jun Zhang·Jian-Wei Pan
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Abstract

Improving the phase resolution of interferometry is crucial for high-precision measurements of various physical quantities. Systematic phase errors dominate the phase uncertainties in most realistic optical interferometers. Here we propose and experimentally demonstrate a weak measurement scheme to considerably suppress the phase uncertainties by the direct amplification of phase shift in optical interferometry. Given an initial ultra-small phase shift between orthogonal polarization states, we observe the phase amplification effect with a factor of 388. Our weak measurement scheme provides a practical approach to significantly improve the interferometric phase resolution, which is favorable for precision measurement applications.

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Li Li, Yuan Li, You-Lang Zhang, Sixia Yu, Chao-Yang Lu, Nai-Le Liu, Jun Zhang, Jian-Wei Pan. 2018-03-21. Phase amplification in optical interferometry with weak measurement. https://doi.org/10.1103/physreva.97.033851

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