Quantum Networking using Waveguide Quantum Electrodynamics

Abstract

The architectural principle of modularity enables the construction of complex systems from simpler components, each responsible for a particular function. The quantum computer is an intricate system comprising fragile, error-prone parts known as qubits. Entanglement distribution across a network of non-local processing modules facilitates robust and extensible quantum computation. In modular quantum architectures, photons are natural quantum information carriers which propagate through interconnects between processing nodes. In this thesis, we engineer a quantum interconnect between superconducting modules underpinned by the physics of waveguide Quantum Electrodynamics (wQED). First, we realize a multi-qubit module that exploits quantum interference to emit microwave photons into a waveguide with a specified propagation direction. Next, we construct the quantum interconnect by coupling two modules to a common waveguide and demonstrate directional (chiral) photon emission and absorption. Finally, using this chiral quantum interconnect, we generate remote entanglement, establishing a key resource for distributed quantum computation in an all-to-all network architecture.