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arXiv · 2610.01227

Experimental quantification of quantum coherence for a set of quantum states

Tianle Zheng·Liangsheng Li·Wenting Zhou·Chengjie Zhang
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Abstract

We present a direct experimental verification of quantum coherence for a set of quantum states in a basis-independent manner. We find that the theory of quantum coherence for a set of quantum states matches our experimental results perfectly and can be applied to protocols like BB84 and quantum secure direct communication. Using a Sagnac interferometer, we experimentally quantify the quantum coherence for two sets of experimental states. Moreover, we introduce a novel application of set coherence, illustrating that the states employed in the BB84 protocol exhibit maximal set coherence. Our results pave the way for wider applications of quantum coherence for a set of quantum states, including quantum key distribution protocols and probabilistic quantum cloning.

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Tianle Zheng, Liangsheng Li, Wenting Zhou, Chengjie Zhang. 2026-10-01. Experimental quantification of quantum coherence for a set of quantum states. https://doi.org/10.1103/physreva.111.042426

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