aiqbench analysis
This research presents a modular architecture for quantum error correction that significantly reduces physical qubit overhead compared to standard planar surface codes. By utilizing sparse boundary connections between flat modules, the approach enables high-rate encoding and efficient fault-tolerant logic without sacrificing fabrication simplicity. The findings suggest a viable pathway toward scalable universal quantum computing architectures by decoupling logical code density from physical layout constraints.
Low-Overhead Quantum Error Correction with Boundary-Connected Planar Modules
arXiv:2610.03682v1 Announce Type: new Abstract: Realizing practical quantum computers requires quantum error correction, but the most widely implemented approach, the planar surface code, demands a substantial physical qubit overhead. Here, we demonstrate that partitioning quantum processors into manageable, flat modules with non-local inter-module connections provides a natural solution. By wiring sparse, static boundary connections between Euclidean planar modules, we construct modular hyperbolic surface and color codes, based on new families of semi-hyperbolic codes. Using modular syndrome extraction circuits and efficient neural network and matching decoders, our circuit-level simulations show that this modular memory design can reduce the physical qubit overhead by tenfold or more compared to the surface code, even under elevated inter-module seam error rates. Projecting to larger system sizes, we find modular codes with encoding rate $k/n=1/16$ and distance $d\geq 22$, exceeding both the rate and distance of the $[[288,12,18]]$ two-gross bivariate bicycle code while using mostly nearest-neighbor gates within planar modules, and implying an over $30\times$ overhead reduction relative to surface codes. We develop fault-tolerant walking circuits for implementing logic via code automorphisms, which we co-design with low-weight, highly symmetrical logical bases and a modular extractor system that is $\approx 4.5\times$ smaller than the code itself. Combining these methods, our modular memory can be used as dense storage in a universal fault-tolerant architecture, unlocking the efficiency of high-rate codes without sacrificing the fabrication advantages of planar modules.
Authors:Oscar Higgott, Hasan Sayginel, Francisco J.H. Heras, Zhiyang He, Tomas Jochym-O'Connor, Andrew W. Senior, Lei M. Zhang, Thomas Edlich, James S. Spencer, Matt McEwen, Craig Gidney, Johannes Bausch, Pushmeet Kohli, Hartmut Neven
Abstract:Realizing practical quantum computers requires quantum error correction, but the most widely implemented approach, the planar surface code, demands a substantial physical qubit overhead. Here, we demonstrate that partitioning quantum processors into manageable, flat modules with non-local inter-module connections provides a natural solution. By wiring sparse, static boundary connections between Euclidean planar modules, we construct modular hyperbolic surface and color codes, based on new families of semi-hyperbolic codes. Using modular syndrome extraction circuits and efficient neural network and matching decoders, our circuit-level simulations show that this modular memory design can reduce the physical qubit overhead by tenfold or more compared to the surface code, even under elevated inter-module seam error rates. Projecting to larger system sizes, we find modular codes with encoding rate $k/n=1/16$ and distance $d\geq 22$, exceeding both the rate and distance of the $[[288,12,18]]$ two-gross bivariate bicycle code while using mostly nearest-neighbor gates within planar modules, and implying an over $30\times$ overhead reduction relative to surface codes. We develop fault-tolerant walking circuits for implementing logic via code automorphisms, which we co-design with low-weight, highly symmetrical logical bases and a modular extractor system that is $\approx 4.5\times$ smaller than the code itself. Combining these methods, our modular memory can be used as dense storage in a universal fault-tolerant architecture, unlocking the efficiency of high-rate codes without sacrificing the fabrication advantages of planar modules.
arXiv:2610.03682 [quant-ph]
(or arXiv:2610.03682v1 [quant-ph] for this version)
https://doi.org/10.48550/arXiv.2610.03682 arXiv-issued DOI via DataCite (pending registration)
Full text under the publisher's open licence · 272 words
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