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arXiv · 2504.10591

Lattice Surgery Compilation Beyond the Surface Code

Laura S. Herzog·Lucas Berent·Aleksander Kubica·Robert Wille
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Abstract

Large-scale fault-tolerant quantum computation requires compiling logical circuits into physical operations tailored to a given architecture. Prior work addressing this challenge has mostly focused on the surface code and lattice surgery schemes. In this work, we broaden the scope by considering lattice surgery compilation for topological codes beyond the surface code. We begin by defining a code substrate - a blueprint for implementing topological codes and lattice surgery. We then abstract from the microscopic details and rephrase the compilation task as a mapping and routing problem on a macroscopic routing graph, potentially subject to substrate-specific constraints. We explore specific substrates and codes, including the color code and the folded surface code, providing detailed microscopic constructions. For the color code, we present numerical simulations analyzing how design choices at the microscopic and macroscopic levels affect the depth of compiled logical $\mathrm{CNOT}+\mathrm{T}$ circuits. An open-source code is available on GitHub https://github.com/cda-tum/mqt-qecc.

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Laura S. Herzog, Lucas Berent, Aleksander Kubica, Robert Wille. 2025-08-01. Lattice Surgery Compilation Beyond the Surface Code. https://doi.org/10.1109/qce65121.2025.00061

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