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arXiv · 2608.04780

Demonstrating advantages of dynamic quantum circuits on a hybrid superconducting qubit-cavity processor

Abstract

Dynamic quantum circuits (DQCs) provide a hardware-efficient route to quantum computing by reducing physical-qubit overhead and compressing circuit topology through mid-circuit measurements, qubit reset and reuse, and classical feed-forward control. Here, we demonstrate the advantages of DQCs on a single hybrid superconducting qubit-cavity processor by implementing a hierarchy of algorithms with increasing complexity. This hybrid architecture consists of a high-dimensional cavity qudit serving as the computational register and a dispersively coupled superconducting transmon ancilla that is repeatedly measured, reset, and reused to enable dynamic control. Using this device, we implement a 10-bit Bernstein-Vazirani algorithm with an average success probability of 82%, surpassing state-of-the-art dynamic and static implementations in both scale and performance; an 8-bit quantum phase-estimation protocol with estimation errors below 10-3; and the first dynamic-circuit implementation of Shor's algorithm on a superconducting platform, factoring 15 over all coprime bases with squared statistical overlap values above 99.8%. These results provide concrete benchmarks for future DQC implementations and highlight the versatile advantages of DQCs with the hybrid qubit-qudit architecture, establishing it as a promising route toward scalable, programmable quantum computation.

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Hongbo Wu, Ling Hu, Jiasheng Mai, Munan Zhang, Libo Zhang, Yanyan Cai, Xiaowei Deng, Pan Zheng, Zhongchu Ni, Song Liu, Kun Fang, Dapeng Yu, Yuan Xu. 2026-08-05. Demonstrating advantages of dynamic quantum circuits on a hybrid superconducting qubit-cavity processor. https://arxiv.org/abs/2608.04780

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