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arXiv · 2502.16132

A Constant Rate Quantum Computer on a Line

Craig Gidney·Thiago Bergamaschi
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Abstract

We prove by construction that the Bravyi-Poulin-Terhal bound on the spatial density of stabilizer codes does not generalize to stabilizer circuits. To do so, we construct a fault tolerant quantum computer with a coding rate above 5% and quasi-polylog time overhead, out of a line of qubits with nearest-neighbor connectivity, and prove it has a threshold. The construction is based on modifications to the tower of Hamming codes of Yamasaki and Koashi (Nature Physics, 2024), with operators measured using a variant of Shor's measurement gadget.

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Craig Gidney, Thiago Bergamaschi. 2025-02-22. A Constant Rate Quantum Computer on a Line. https://arxiv.org/abs/2502.16132

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