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arXiv · 1910.10933

Direct measurement of a nonlocal entangled quantum state

Wei-Wei Pan·Xiao-Ye Xu·Yaron Kedem·Qin-Qin Wang·Zhe Chen·Munsif Jan·Kai Sun·Jin-Shi Xu·Yong-Jian Han·Chuan-Feng Li·Guang-Can Guo
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Abstract

Entanglement and wave function description are two of the core concepts that make quantum mechanics such a unique theory. A method to directly measure the wave function, using Weak Values, was demonstrated by Lundeen et al., Nature \textbf{474}, 188(2011). However, it is not applicable to a scenario of two disjoint systems, where nonlocal entanglement can be a crucial element since that requires obtaining the Weak Values of nonlocal observables. Here, for the first time, we propose a method to directly measure a nonlocal wave function of a bipartite system, using Modular Values. The method is experimentally implemented for a photon pair in a hyper-entangled state, i.e. entangled both in polarization and momentum degrees of freedom.

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Wei-Wei Pan, Xiao-Ye Xu, Yaron Kedem, Qin-Qin Wang, Zhe Chen, Munsif Jan, Kai Sun, Jin-Shi Xu, Yong-Jian Han, Chuan-Feng Li, Guang-Can Guo. 2019-10-24. Direct measurement of a nonlocal entangled quantum state. https://doi.org/10.1103/physrevlett.123.150402

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