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arXiv:2512.04953

Circuit Quantum Acoustodynamics in a Scalable Phononic Integrated Circuit Architecture

Weiting Wang, Lintao Xiao, Bo Zhang, Yu Zeng, Ziyue Hua, Chuanlong Ma, Hongwei Huang, Yifang Xu, Jia-Qi Wang, Guangming Xue, Haifeng Yu, Xin-Biao Xu, Chang-Ling Zou, Luyan Sun

quant-phSubmitted Dec 4, 2025• Announced Dec 5, 2025
arXivHTMLPDF

Abstract

Previous demonstrations of quantum acoustic systems have been limited to isolated devices, with limited capability to route phonons and interconnect multi-port acoustic elements for further extension. Here, we demonstrate a scalable architecture for circuit quantum acoustodynamics (cQAD) by integrating superconducting qubits with suspension-free phononic integrated circuits (PnICs). Coherent coupling between tunable transmon qubits and waveguide-integrated phononic cavities, including Fabry-Perot cavities via monolithic integration and microring cavities via flip-chip assembly, has been achieved, producing a pronounced enhancement of phonon emission with a Purcell factor of ~19. These devices represent elementary building blocks for scalable phononic circuits, establishing the foundation for phonon-based quantum information processors and the testbed for novel quantum acoustic phenomena.

Comments
8 pages, 3 figures

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