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arXiv · 2605.14656

Blind Quantum Computation on a Modular Superconducting Processor

Yongxin Song·Johannes Knörzer·Kieran Dalton·Andreas Wallraff·Jean-Claude Besse
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Abstract

Current cloud-based quantum processors offer access to advanced hardware hosted on a remote server, but do not guarantee data or algorithm privacy. Blind quantum computation provides information-theoretic privacy by enabling a client to execute an algorithm without disclosing information about either the task or the final result. Here, we execute a measurement-based blind quantum computation protocol on a superconducting processor comprising two flip-chip-bonded modules, one acting as a server and the other as a client. The server generates a two-dimensional cluster state and forwards it to the client. Using this resource, the client implements a universal gate set with only adaptive single-qubit rotations and measurements. To illustrate this approach, we execute a three-qubit instance of the Deutsch-Jozsa algorithm. We analyze the server's quantum state after each rotation of a measurement-based single-qubit gate to verify that negligible information about the computation is revealed to the server, consistent with the one-way flow of information that guarantees blindness. This proof-of-principle demonstration establishes key elements of blind quantum computation in superconducting-circuit architectures, indicating that intermediate-scale implementations of blind protocols may become feasible with realistic near-term improvements in gate fidelities.

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Yongxin Song, Johannes Knörzer, Kieran Dalton, Andreas Wallraff, Jean-Claude Besse. 2026-05-14. Blind Quantum Computation on a Modular Superconducting Processor. https://arxiv.org/abs/2605.14656

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