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arXiv · 2501.10291

Low-overhead Magic State Circuits with Transversal CNOTs

Nicholas Fazio·Mark Webster·Zhenyu Cai
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Abstract

With the successful demonstration of transversal CNOTs in many recent experiments, it is the right moment to examine its implications on one of the most critical parts of fault-tolerant computation -- magic state preparation. Using an algorithm that can recompile and simplify a circuit of consecutive multi-qubit phase rotations, we manage to construct fault-tolerant circuits for CCZ, CS and T states with much lower CNOT depths and qubit counts than before and minimal T-depth for the given workspace. These circuits can play crucial roles in fault-tolerant computation with transversal CNOTs, and we hope that the algorithms and methods developed in this paper can be used to further simplify other protocols in similar contexts.

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Nicholas Fazio, Mark Webster, Zhenyu Cai. 2025-01-17. Low-overhead Magic State Circuits with Transversal CNOTs. https://arxiv.org/abs/2501.10291

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