Satellite CV-QKD

ended

Quantum Key Distribution (QKD) allows two parties to exchange a cryptographic key in an unconditionally secure way. Thus, this system will be secure even after the development of a quantum computer, which is thought to efficiently break current key exchange mechanisms based on public-key cryptography. While most current QKD implementations are fiber-based, its intrinsic limitation to some hundred kilometers, due to fiber losses, makes satellite QKD a crucial technology for the establishment of a secure link at a world-wide scale. The research on satellite QKD has mainly focused on discrete variable (DV) protocols, which are less sensitive to channel transmission but require single photon detection technology. Continuous variable (CV) protocols, on the other hand, are based on standard telecom detection technology, which is much faster and more efficient. Recently, CV protocols have shown to work well in high losses fiber-based environments. This action aims to extend the CV scheme to the free-space domain, implementing a full, self-referenced CV-QKD scheme on a free-space channel, as a first step for a future satellite implementation of such technology.