Placing and routing quantum LDPC codes in multilayer superconducting hardware

• URL: http://arxiv.org/abs/2507.23011v2
• Date: Sat, 13 Sep 2025 00:02:56 GMT
• Title: Placing and routing quantum LDPC codes in multilayer superconducting hardware
• Authors: Melvin Mathews, Lukas Pahl, David Pahl, Vaishnavi L. Addala, Catherine Tang, William D. Oliver, Jeffrey A. Grover,
• Abstract summary: We develop Hardware-Aware Layout, HAL: a robust, efficient runtime algorithm.<n> HAL generates around 150 explicit layouts of quantum low-density parity-check (qLDPC) codes.<n>We lay out highly nonlocal qLDPC code families that achieve competitive tradeoffs between hardware complexity and logical efficiency.
• Score: 0.6713975160553138
• License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
• Abstract: Quantum error-correcting codes with asymptotically lower overheads than the surface code require nonlocal connectivity. Leveraging multilayer routing and long-range coupling capabilities in superconducting qubit hardware, we develop Hardware-Aware Layout, HAL: a robust, runtime-efficient heuristic algorithm that automates and optimizes the placement and routing of arbitrary codes. Using HAL, we generate around 150 explicit layouts of quantum low-density parity-check (qLDPC) codes with topological structure -- such as the bivariate bicycle codes and the open-boundary tile codes -- and find that removing the periodic boundaries significantly lowers the hardware complexity with only a moderate reduction of logical efficiency. We also lay out highly nonlocal qLDPC code families -- quantum radial and Tanner codes -- that achieve competitive tradeoffs between hardware complexity and logical efficiency. Based on our findings, we anticipate many novel qLDPC codes to be realizable on near-term superconducting qubit hardware and inform future directions for the co-design of quantum devices and fault-tolerant architectures.

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