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arXiv · 2009.13915

Fully autocompensating high-dimensional quantum cryptography by optical phase conjugation

Jesús Liñares·Xesús Prieto-Blanco·Daniel Balado·Gabriel M. Carral
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Abstract

We present a bidirectional quantum communication system based on optical phase conjugation for achieving fully autocompensating high-dimensional quantum cryptography. We prove that random phase shifts and couplings among 2N spatial and polarization optical modes described by SU(2N) transformations due to perturbations are autocompensated after a single round trip between Alice and Bob. Bob can use a source of single photons or, alternatively, coherent states and then Alice attenuates them up to a single photon level, and thus non-perturbated 1-qudit states are generated for high-dimensional QKD protocols, as the BB84 one, of a higher security.

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Jesús Liñares, Xesús Prieto-Blanco, Daniel Balado, Gabriel M. Carral. 2020-09-29. Fully autocompensating high-dimensional quantum cryptography by optical phase conjugation. https://doi.org/10.1103/physreva.103.043710

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