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arXiv · 2508.21178

Communication scenario enables robust self-testing of n-party Greenberger-Horne-Zeilinger basis measurements

Barnik Bhaumik·Sagnik Ray·Debashis Saha
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Abstract

Entangled basis measurements play a crucial role in distributing quantum entanglement between parties across a quantum network. In this work, we adopt a semi-device-independent approach that enables the self-testing of n-qubit Greenberger-Horne-Zeilinger (GHZ) basis measurements without requiring shared entanglement between distant parties. Our method relies solely on input-output statistics from a communication scenario involving n spatially separated senders, each receiving two bits of input, and a single receiver with no input. We analyze the robustness of the proposed self-testing protocol. Additionally, we introduce a protocol for robust self-testing of the three-outcome partial Bell basis measurement that is easily implementable in an optical setup.

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Barnik Bhaumik, Sagnik Ray, Debashis Saha. 2025-08-28. Communication scenario enables robust self-testing of n-party Greenberger-Horne-Zeilinger basis measurements. https://doi.org/10.1103/mvmn-fzq7

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