Quantum Communication and Quantum Internet

Stephanie Wehner

Quantum network technology Prof Dr Stephanie Wehner, Director of the European Quantum Internet Alliance, explains how quantum network technology and a quantum internet could revolutionise communication and connectivity. The internet, an intricate network connecting devices across the globe with classical communication, has profoundly shaped our world. We now stand on the brink of a new type of internet. Imagine an evolution of the internet, one that intertwines the principles of quantum mechanics with our existing digital technology. This is the vision of a quantum internet - an innovation that promises to redefine our understanding of communication and connectivity. Working in tandem with our traditional ‘classical’ internet, a quantum internet would connect quantum devices globally. Such a network would unlock capabilities that are fundamentally unattainable through classical communication alone. Take, for instance, Quantum Key Distribution (QKD), a striking application of quantum communication. QKD allows two distant nodes to create an encryption key guarded by the immutable principles of quantum mechanics.

Alexander V. Sergienko, Villoresi, Paolo, Saverio Pascazio

Koji Azuma, Akihiro Mizutani, Hoi‐Kwong Lo

The quantum internet holds promise for achieving quantum communication-such as quantum teleportation and quantum key distribution (QKD)-freely between any clients all over the globe, as well as for the simulation of the evolution of quantum many-body systems. The most primitive function of the quantum internet is to provide quantum entanglement or a secret key to two points efficiently, by using intermediate nodes connected by optical channels with each other. Here we derive a fundamental rate-loss trade-off for a quantum internet protocol, by generalizing the Takeoka-Guha-Wilde bound to be applicable to any network topology. This trade-off has essentially no scaling gap with the quantum communication efficiencies of protocols known to be indispensable to long-distance quantum communication, such as intercity QKD and quantum repeaters. Our result-putting a practical but general limitation on the quantum internet-enables us to grasp the potential of the future quantum internet.

Ming-Xing Luo

Victoria Lipińska

The Internet as we know it has had an immense impact on the way we communicate. We can now do it faster and more securely than ever before. Enabling quantum communication between any two points on Earth is the next step towards even more secure communication. This is the goal of the quantum internet. Although it is hard to predict all of the applications for the quantum internet, many protocols running on a network connecting nodes able to process qubits have already been identified. Typically, these applications require many qubits to be realized, a requirement which will not likely be met in the early quantum internet.

Riccardo Bassoli, Holger Boche, Christian Deppe +4 more