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arXiv · 2508.10442

High-dimensional autocompensating discrete modulation CV-QKD protocol in optical fibers

Alexandre Vázquez-Martínez·Xesús Prieto-Blanco·Eduardo F. Mateo·Jesús Liñares
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Abstract

In this work we present a high-dimensional discrete modulated CV-QKD protocol, with dimension 2N , in optical fibers, where N is the number of optical modes. We use N-dimensional product states of weak coherent states that undergo perturbations along optical fibers and that are cancelled in a passive way (autocompensation) and then measured by a standard balanced homodyne detection. We analyze the security of this high-dimensional protocol when an intercept and resend attack is implemented with simultaneous homodyne measurement in both quadratures and the resulting secure key gains are calculated showing a significative increase with dimension.

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Alexandre Vázquez-Martínez, Xesús Prieto-Blanco, Eduardo F. Mateo, Jesús Liñares. 2025-08-14. High-dimensional autocompensating discrete modulation CV-QKD protocol in optical fibers. https://arxiv.org/abs/2508.10442

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