Proposal of cavity quantum acoustodynamics platform based on lithium niobate-on-sapphire chip

作者：Xin‐Biao Xu, Lintao Xiao, Bo Zhang, Weiting Wang, Jia-Qi Wang, Yan Zeng, Yuan-Hao Yang, Baozhen Wang, Xiaoxuan Pan, Guang-Can Guo, Luyan Sun, Chang-Ling Zou · 发表于：Journal of Applied Physics · 年份：2026 · DOI：10.1063/5.0307570 · 被引用次数：1 · 研究领域：Mechanical and Optical Resonators、Quantum Mechanics and Non-Hermitian Physics、Acoustic Wave Resonator Technologies

A scalable hybrid cavity quantum acoustodynamics (QAD) platform is proposed. The architecture integrates superconducting transmon qubits with phononic integrated circuits on a single chip made by a lithium niobate-on-sapphire substrate. The platform supports tightly confined and guided phononic modes in unsuspended waveguides and microring structures, while the superconducting qubits reside on the sapphire substrate. Efficient piezoelectric coupling between the phononic modes and transmon qubits can be achieved using interdigital transducers as part of the qubit’s shunt capacitance. Numerical calculations demonstrate the feasibility of achieving strong coupling between the phononic microring resonator and the transmon qubit. Remarkably, we show that a single pair of interdigital transducer fingers is sufficient to yield a coupling strength of g/2π≈1.3 MHz for the quasi-Love mode. This hybrid cavity QAD platform opens up new opportunities for quantum information processing and the study of novel quantum acoustic phenomena.