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arXiv · 2510.05221

Fault-tolerant interfaces for modular quantum computing on diverse qubit platforms

Frederik K. Marqversen·Gefen Baranes·Maxim Sirotin·Johannes Borregaard
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Abstract

Modular architectures offer a scalable path toward fault-tolerant quantum computing by interconnecting smaller quantum processing units (QPUs) provided that high-rate, fault-tolerant interfaces can be realized across modules. We present a comprehensive analysis and comparison of known and new methods for establishing such interfaces, including lattice surgery, transversal gates, and novel grow-and-distil protocols based on code growing and logical distillation. Using the surface code, we identify optimal interface strategies across a wide range of hardware parameters, such as gate fidelities, entangling rates, and memory resources, and estimate the requirements to achieve logical error rates of $10^{-6}$ and $10^{-12}$. Our results establish when the interface become a bottleneck in the computation and provide guidance for experimental implementations with superconducting, atomic, and solid-state hardware.

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Frederik K. Marqversen, Gefen Baranes, Maxim Sirotin, Johannes Borregaard. 2025-10-06. Fault-tolerant interfaces for modular quantum computing on diverse qubit platforms. https://doi.org/10.1103/ds45-fm9n

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