Quantum key distribution session with 16-dimensional photonic states

TL;DR

This paper demonstrates a fully automated quantum key distribution session using 16-dimensional photonic states, showcasing the potential for higher-dimensional quantum cryptography in real-world applications.

Contribution

First experimental implementation of high-dimensional (16D) QKD using programmable spatial light modulators for dynamic state generation.

Findings

Successful 16D QKD session performed

Enhanced security potential with higher dimensions

Dynamic state generation demonstrated

Abstract

The secure transfer of information is an important problem in modern telecommunications. Quantum key distribution (QKD) provides a solution to this problem by using individual quantum systems to generate correlated bits between remote parties, that can be used to extract a secret key. QKD with D-dimensional quantum channels provides security advantages that grow with increasing D. However, the vast majority of QKD implementations has been restricted to two dimensions. Here we demonstrate the feasibility of using higher dimensions for real-world quantum cryptography by performing, for the first time, a fully automated QKD session based on the BB84 protocol with 16-dimensional quantum states. Information is encoded in the single-photon transverse momentum and the required states are dynamically generated with programmable spatial light modulators. Our setup paves the way for future developments in the field of experimental high-dimensional QKD.