Order from Disorder: Control of Multi-Qubit Spin Registers in Diamond

Electron spin qubits associated with individual solid-state defects can exhibit exceptional coherence and bright optical interfaces. Furthermore, their magnetic interactions with nuclear spins in the host material present a resource for multi-qubit registers. They have thus emerged as powerful systems with which to develop quantum technologies. In this thesis, we develop a toolbox for the precise control of multi-qubit spin systems associated with single nitrogen-vacancy centres in diamond. We utilise this platform to explore a number of avenues in quantum science: networks, computation, sensing, and simulation. Our findings provide new insights towards the goal of distributed quantum computation, and establish a programmable solid-state-spin quantum simulator for studying many-body physics.