arXiv:1306.1027

Experimental test of the tradeoff relation in weak measurement

Geng Chen, Yang Zou, Xiao-Ye Xu, Jian‐Shun Tang, Yulong Li, Yong‐Jian Han, Chuan‐Feng Li, Guang-Can Guo Hai-qiao Ni, Ying Yu, Mi-Feng Li, Guowei Zha, Zhichuan Niu

Published Jun 5, 2013• 0 citations

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Abstract

An upper bound between the information gain and state reversibility of weak measurement was first developed by Y. K. Cheong and S. W. Lee [Phys. Rev. Lett. 109, 150402 (2012)]. Their results are valid for arbitrary d-level quantum systems. In light of the commonly used qubit system in quantum information, a sharp tradeoff relation can be obtained. In this letter, this tradeoff relation is experimentally verified with polarization encoded single photons from a quantum dot. Furthermore, a complete traversal of weak measurement operators is realized, and the mapping to the least upper bound of this tradeoff relation is obtained. Our results complement the theoretical work and provide a universal ruler for the characterization of weak measurements.

DOI: 10.48550/arxiv.1306.1027

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