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arXiv · 2204.01442

Complete hyperentangled Bell states analysis for polarization-spatial-time-bin degrees of freedom with unity fidelity

Xin-Jie Zhou·Wen-Qiang Liu·Yan-Bei Zheng·Hai-Rui Wei·Fang-Fang Du
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Abstract

Hyperentangled states can outperform their classical counterparts on solving certain tasks. Here we present a simplified scheme for completely distinguishing two-photon hyperentangled Bell states in polarization, spatial, and time-bin degrees of freedom (DOFs). Unity fidelity can be achieved in principle without strong couple limitation between photon and quantum dot (QD), and the incomplete and imperfect QD-cavity interactions are prevented by single-photon detectors. In addition, auxiliary photons or DOFs are not required in our scheme. The necessary linear optical elements are fewer than the parity-check-based one.

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Xin-Jie Zhou, Wen-Qiang Liu, Yan-Bei Zheng, Hai-Rui Wei, Fang-Fang Du. 2022-04-04. Complete hyperentangled Bell states analysis for polarization-spatial-time-bin degrees of freedom with unity fidelity. https://doi.org/10.1002/andp.202100509

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