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arXiv · 2203.02989

Security of a High Dimensional Two-Way Quantum Key Distribution Protocol

Walter O. Krawec
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Abstract

Two-way quantum key distribution protocols utilize bi-directional quantum communication to establish a shared secret key. Due to the increased attack surface, security analyses remain challenging. Here we investigate a high-dimensional variant of the Ping Pong protocol and perform an information theoretic security analysis in the finite-key setting. Our methods may be broadly applicable to other QKD protocols, especially those relying on two-way channels. Along the way, we show some fascinating benefits to high-dimensional quantum states applied to two-way quantum communication.

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Walter O. Krawec. 2022-03-06. Security of a High Dimensional Two-Way Quantum Key Distribution Protocol. https://arxiv.org/abs/2203.02989

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