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arXiv · 2009.08584

Characterizing Bell state analyzer using weak coherent pulses

Donghwa Lee·Young-Wook Cho·Hyang-Tag Lim Sang-Wook Han·Hojoong Jung·Sung Moon·Yong-Su Kim
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Abstract

Bell state analyzer (BSA) is one of the most crucial apparatus in photonic quantum information processing. While linear optics provide a practical way to implement BSA, it provides unavoidable errors when inputs are not ideal single-photon states. Here, we propose a simple method to deduce the BSA for single-photon inputs using weak coherent pulses. By applying the method to Reference-Frame-Independent Measurement-Device-Independent Quantum Key Distribution, we experimentally verify the feasibility and effectiveness of the method.

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Donghwa Lee, Young-Wook Cho, Hyang-Tag Lim Sang-Wook Han, Hojoong Jung, Sung Moon, Yong-Su Kim. 2020-09-18. Characterizing Bell state analyzer using weak coherent pulses. https://arxiv.org/abs/2009.08584

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