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arXiv · 2101.01483

Quantum Conference Key Agreement with Photon Loss

Phattharaporn Singkanipa·Pieter Kok
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Abstract

Conference key agreement (CKA) is an information processing task where more than two parties want to share a common secret key. Here, we present a loss-resilient protocol for CKA, based on redundant encoding and error correction. Our protocol provides a speed-up in transmission rate over the existing lossy CKA protocol. However, encoding and error correction come with extra cost. We show that, using photon sources with creation probability p > 0.3, our protocol's secret key rate can overcome the existing protocol's. Hence, high probability entangled photon sources are required for realistic implementation of our loss-resilient protocol.

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Phattharaporn Singkanipa, Pieter Kok. 2021-01-05. Quantum Conference Key Agreement with Photon Loss. https://arxiv.org/abs/2101.01483

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