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arXiv · 2103.14802

Experimental quantum phase discrimination enhanced by controllable indistinguishability-based coherence

Kai Sun·Zheng-Hao Liu·Yan Wang·Ze-Yan Hao·Xiao-Ye Xu·Jin-Shi Xu·Chuan-Feng Li·Guang-Can Guo·Alessia Castellini·Ludovico Lami·Andreas Winter·Gerardo Adesso·Giuseppe Compagno·Rosario Lo Franco
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Abstract

Quantum coherence, a basic feature of quantum mechanics residing in superpositions of quantum states, is a resource for quantum information processing. Coherence emerges in a fundamentally different way for nonidentical and identical particles, in that for the latter a unique contribution exists linked to indistinguishability which cannot occur for nonidentical particles. We experimentally demonstrate by an optical setup this additional contribution to quantum coherence, showing that its amount directly depends on the degree of indistinguishability and exploiting it to run a quantum phase discrimination protocol. Furthermore, the designed setup allows for simulating Fermionic particles with photons, thus assessing the role of particle statistics (Bosons or Fermions) in coherence generation and utilization. Our experiment proves that independent indistinguishable particles can supply a controllable resource of coherence for quantum metrology.

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Kai Sun, Zheng-Hao Liu, Yan Wang, Ze-Yan Hao, Xiao-Ye Xu, Jin-Shi Xu, Chuan-Feng Li, Guang-Can Guo, Alessia Castellini, Ludovico Lami, Andreas Winter, Gerardo Adesso, Giuseppe Compagno, Rosario Lo Franco. 2021-03-27. Experimental quantum phase discrimination enhanced by controllable indistinguishability-based coherence. https://doi.org/10.1073/pnas.2119765119

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