Towards useful computation with neutral-atom quantum processors

Abstract

Quantum computers promise to harness the power of quantum entanglement for transformative advances in cryptography, the computational science of materials, and our understanding of fundamental physics. However, major advances in quantum algorithms, hardware, and error-correction techniques are necessary to realize this technology's full potential. In this thesis we show that co-design---the development of all three components in a mutually informed fashion---can result in significant advantages and enable complex quantum computation. We focus on the reconfigurable-atom-array platform, where qubits are encoded in long-lived atomic states and controlled by laser fields. Quantum entanglement at scale is realized by globally exciting the atoms to strongly-interacting Rydberg states, and we experimentally demonstrate quantum gates with fidelity above 99.5%---high-enough to benefit from error-correction (QEC). Leveraging dynamical qubit connectivity enabled by coherent atom transport, we design hardware-efficient protocols for simulating chemistry models and topological quantum matter. With this approach, we experimentally realize the exotic non-Abelian phase of the Kitaev honeycomb model and probe the emergent dynamics of fermionic particles, engineered to experience strong interactions. Similarly, we also show that the overhead introduced by QEC for classically complex computation can be significantly reduced by designing the quantum circuit and QEC codes together. These advances highlight the utility of the co-design principle and pave the way towards useful quantum computation.