The intriguing genuinely quantum phenomena of quantum entanglement and quantum coherence are the basis of the advantages witnessed in quantum technologies. We investigate their paramount role in the phenomena of superadditivity and superactivation of quantum channel capacities. Importantly, we investigate how their hidden manifestation in the indefinite causal order framework could be harnessed to generate entanglement in quantum networks in a distributed manner. This lays the ground to new ways of looking at future networks in their full quantum nature, and better understanding their potential to achieve unprecedented practical levels.
Distributed quantum computing is one of the most appealing applications in the panorama of Quantum Technologies. In fact, distributed architectures could be our bridge to step beyond the current NISQ era. This is why we work to achieve large-scale integration of quantum technologies. By inter-connecting spatially distributed quantum processors, we would achieve a scalable architecture resistant to noise. Our roadmap towards a distributed quantum computing ecosystem is outlined in the figure on the left. Each layer from the above picture is of crucial importance to be able to perform quantum algorithm over a distributed architecture. We detail this in [CuoCacCal-20].
The design of complex systems – such as communication networks – is commonly simplified through an abstract model, which enables the characterization and standardization of the different functionalities by abstracting from the particulars of the underlying technologies. When it comes to the Quantum Internet a standard model is missing. Moreover, the peculiarities of quantum phenomena impose a major paradigm shift and prohibit a one-to-one mapping between classical Internet protocol stack and the Quantum Internet services. Indeed, the key resource for quantum communications, i.e., the phenomenon of quantum entanglement, revolutionizes the very concept of communication network. Specifically, entanglement gives birth to a wider concept of connectivity that affects the entire protocol stack functionalities impose new challenges for the network design. For an in depth discussion click [IllCalMan21].
Our milestones towards the Quantum Internet.