High-dimensional quantum key distribution using dispersive optics

TL;DR

This paper introduces a high-dimensional quantum key distribution protocol using dispersive optics that is secure, compatible with fiber channels, and capable of achieving high secret-key rates up to 100 Mbps.

Contribution

It presents a novel dispersion-based high-dimensional QKD protocol with multiple implementations and a practical heralded qudit source for high-rate secure communication.

Findings

Secure against coherent attacks

Achieves secret-key rates up to 100 Mbps

Compatible with standard fiber telecom infrastructure

Abstract

We propose a high-dimensional quantum key distribution (QKD) protocol that employs temporal correlations of entangled photons. The security of the protocol relies on measurements by Alice and Bob in one of two conjugate bases, implemented using dispersive optics. We show that this dispersion-based approach is secure against general coherent attacks. The protocol is additionally compatible with standard fiber telecommunications channels and wavelength division multiplexers. We offer multiple implementations to enhance the transmission rate and describe a heralded qudit source that is easy to implement and enables secret-key generation at up to 100 Mbps at over 2 bits per photon.