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arXiv · 2409.04204

Twin-field-based multi-party quantum key agreement

Venkat Abhignan·R. Srikanth
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Abstract

Quantum key distribution (QKD) can secure cryptographic communication between two distant users, as guaranteed by the laws of quantum mechanics rather than computational assumptions. The twin-field scheme, which employs counter-propagated weak coherent light pulses, doubles the secure distance of standard QKD without using quantum repeaters. Here, we study a method to extend the twin-field key distribution protocol to a scheme for multi-party quantum key agreement. We study our protocol's security using a minimum error discrimination analysis and derive the asymptotic key rate based on the entanglement-based source-replacement scheme. We also simulate it on the ANSYS Interconnect platform with optical components to study the protocol's performance in certain practical situations.

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Venkat Abhignan, R. Srikanth. 2024-09-06. Twin-field-based multi-party quantum key agreement. https://doi.org/10.1364/josab.541759

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