Advancing On-Chip Continuous-Variable Quantum Key Distribution Solutions

Quantum key distribution (QKD) enables secure secret key exchange with information-theoretic security by leveraging the principles of quantum mechanics. Continuous-variable QKD (CV-QKD), which utilizes coherent states and coherent detection, has gained attention as a promising approach due to its seamless integration with existing telecommunications networks. CV-QKD systems, which are built with standard telecommunication components, open the door - through photonic integration technology - to the development of devices that are more affordable, compact, and energy efficient. This paper reviews the current state of the art and highlights our recent progress toward fully integrated CV-QKD systems.