Abstract
Neutral-atom arrays have recently emerged as a promising platform for quantum information processing. One important remaining roadblock for the large-scale application of these systems is the ability to perform error-corrected quantum operations. To entangle the qubits in these systems, atoms are typically excited to Rydberg states, which could decay or give rise to various correlated errors that cannot be addressed directly through traditional methods of fault-tolerant quantum computation. In this work, we provide the first complete characterization of these sources of error in a neutral-atom quantum computer and propose hardware-efficient, fault-tolerant quantum computation schemes that mitigate them. Notably, we develop a novel and distinctly efficient method to address the most important errors associated with the decay of atomic qubits to states outside of the computational subspace. These advances allow us to significantly reduce the resource cost for fault-tolerant quantum computation compared to existing, general-purpose schemes. Our protocols can be implemented in the near term using state-of-the-art neutral-atom platforms with qubits encoded in both alkali and alkaline-earth atoms.
- Received 6 June 2021
- Revised 3 February 2022
- Accepted 12 April 2022
DOI:https://doi.org/10.1103/PhysRevX.12.021049
Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article’s title, journal citation, and DOI.
Published by the American Physical Society
Physics Subject Headings (PhySH)
Popular Summary
Throughout human history, the specialization of labor has led to remarkable advances in knowledge and productivity. Analogously, in quantum information, general-purpose quantum error correction protocols can only be as efficient as the society in which every member has the same duties. Indeed, despite major efforts across different platforms, most general-purpose approaches for error-corrected quantum computation are still out of reach even for the most advanced systems because of significant overhead in extra qubits and quantum gates. Motivated by these considerations, we propose and analyze the specialized design of fault-tolerant quantum computation protocols tailored to a quantum computer built from arrays of neutral Rydberg atoms, atoms in which one electron is in a very highly excited state.
Inspired by recent experimental advances in quantum control of arrays exceeding 200 atoms, our work provides the first comprehensive study of the relevant error channels in this system and identifies several decay mechanisms that are challenging to address using traditional, general-purpose techniques. We exploit the specific structure of the error model to considerably simplify several error-correction requirements, and we make use of important features of neutral atoms to greatly facilitate the key steps in our protocols.
Our approach to error correction for neutral Rydberg array quantum computation is dramatically more efficient than existing methods and could be implemented in near-term experiments involving hundreds of programmable atoms.
