Advanced Quantum Communication System Based on Reference-Frame Independent Configuration

Quantum Technologies are revolutionizing the world as we know it, influencing and reshaping plenty of different areas, from physics to engineering, determining in some extent also daily life when security is taken into consideration. This process began more than a century ago and has not yet stopped. With the growing computational power of supercomputers and now Quantum Computing, security has become more then ever vulnerable. The only possible way to face this threat is to build equally powerful and secure encryption mechanisms based on the same physical structure. This is the role of Quantum Key Distribution. This technology is rapidly expanding across global networks, aiming to increase the level of robustness of actual classical communication, despite the resources available at the present and even considering the hacking power at disposal in the future. Relying on fundamental postulates of Quantum Mechanics, QKD guarantees unbeatable secrecy, becoming a fundamental asset for the telecommunication infrastructure. In an effort to improve these protocols, making them reliable to function in harsh conditions, several different alternatives have been investigated since the first ever invented, more than forty years ago. Among these, the class of Reference Frame Independent protocols is gaining more and more interest, allowing to relax the constraints in the shared reference frame between the users that typically requires complex control schemes. The protocol described in this doctoral thesis aims to offer a more robust alternative within the family of RFI protocols, exploiting an advanced technique of self calibration of the receiver apparatus, capable of considering physical imperfections in order to distill a cryptographic key with high level of security.