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arXiv · 2202.06168

Observations of the delayed-choice quantum eraser using coherent photons

Sangbae Kim·Byoung S. Ham
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Abstract

Quantum superposition is the cornerstone of quantum mechanics, where interference fringes originate in the self-interference of a single photon via indistinguishable photon characteristics. Wheeler delayed-choice experiments have been extensively studied for the wave-particle duality over the last several decades to understand the complementarity theory of quantum mechanics. The heart of the delayed-choice quantum eraser is in the mutually exclusive quantum feature violating the cause-effect relation. Here, we experimentally demonstrate the quantum eraser using coherent photon pairs by the delayed choice of a polarizer placed out of the interferometer. Coherence solutions of the observed quantum eraser are derived from a typical Mach-Zehnder interferometer, where the violation of the cause-effect relation is due to selective measurements of basis choice.

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Sangbae Kim, Byoung S. Ham. 2022-02-13. Observations of the delayed-choice quantum eraser using coherent photons. https://arxiv.org/abs/2202.06168

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