Modular source for near-infrared quantum communication

TL;DR

This paper introduces a modular, secure, and tunable near-infrared quantum source for QKD, optimized for satellite use, enhancing security and simplifying development for space applications.

Contribution

A novel modular quantum source design utilizing the iPOGNAC polarization scheme, improving security, tunability, and suitability for satellite-based QKD systems.

Findings

Successfully implemented and tested at 800 nm wavelength.

Demonstrated immunity to side-channel and hacking attacks.

Showed simplified development process for space missions.

Abstract

We present a source of states for Quantum Key Distribution (QKD) based on a modular design exploiting the iPOGNAC, a stable, low-error, and calibration-free polarization modulation scheme, for both intensity and polarization encoding. This source is immune to the security vulnerabilities of other state sources such as side channels and some quantum hacking attacks. Furthermore, our intensity modulation scheme allows full tunability of the intensity ratio between the decoy and signal states, and mitigates patterning effects. The source was implemented and tested at the near-infrared optical band around 800 nm, of particular interest for satellite-based QKD. Remarkably, the modularity of the source simplifies its development, testing, and qualification, especially for space missions. For these reasons, our work paves the way for the development of the second generation of QKD satellites that can guarantee excellent performances at higher security levels.