We have now examined every layer of the stack for building and programming a quantum computer. However, we know from the development of classical computers that computers which can communicate with each other through networks are far more useful than computers which are isolated. This naturally raises the question of how to connect quantum computers to one another. How do we perform a CNOT between two qubits, when they’re not even in the same country?

One of the convenient properties of quantum mechanics is that such ‘non-local’ gates can be performed, as long as we consume a shared entangled state for each non-local gate we want to do. This distribution of entanglement is the fundamental task of a quantum internet. However, this distribution of entanglement does more than enable non-local computation. It can be used to replace many of the communication protocols we use today with faster, or inherently private alternatives. Over the course of the next three lectures and two quizzes, David Elkouss will introduce the tasks that a quantum internet can perform better than its classical counterpart, as well as the components that make up these networks.

We hope you enjoy learning about this fascinating new technology.