Scalable Methods for Performant Control of Hyperfine Qubits in Atoms and Ions

Chow, Matthew N. H.

Published Nov 13, 2024• 0 citations

Abstract

Qubits encoded within internal energy levels of atoms and ions have been used to demonstrate high-performance primitives of quantum computing for small numbers of qubits. Yet, the path to achieving sufficient size and fidelity for useful fault-tolerant quantum computation remains daunting. In this dissertation, I present several techniques I developed as steps along this path. These results include high-fidelity, low-loss detection for alkali atoms in optical tweezers, crosstalk-mitigated parallel one-qubit gates, robust entangling gates on trapped ions, and leakage-to-erasure conversion for non-destructive detection of atom loss errors. Through this collection of techniques, I have sought to make full use of the underlying atomic physics to alleviate technical burden in scaling up to large systems while maintaining or improving on qubit control fidelity. I emphasize that all these results are achieved with low technical overhead, allowing for direct implementation in systems at scale.

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