Mechanical resonators are a promising way for interfacing qubits in order to realize hybrid quantum systems that offer great possibilities for applications. Mechanical systems can have very long energy lifetimes, and they can be further interfaced to other systems. Moreover, integration of mechanical oscillator with qubits creates a potential platform for exploration of quantum physics in macroscopic mechanical degrees of freedom. Utilization of high overtone bulk acoustic resonators coupled to superconducting qubits is an intriguing platform towards these goals. These resonators exhibit a combination of high frequency and high quality factors. They can reach their quantum ground state at dilution refrigeration temperatures and they can be strongly coupled to superconducting qubits via their piezoelectric effect. In this report, we demonstrate our system where bulk acoustic phonons of a high overtone resonator are coupled to a transmon qubit in a planar circuit architecture. We show that the bulk acoustic phonons are interacting with the qubit in the simple design architecture at the quantum level, representing further progress towards quantum control of mechanical motion.
Impedance-matched High-Overtone Thickness-Shear Bulk Acoustic Resonators with Scalable Mode Volume
State Key Laboratory of Solid State Microstructures, Department of Materials Science and Engineering, Nanjing University（南京大学固体微结构物理国家重点实验室材料科学与工程系）；Institute for Frontier Science, Nanjing University of Aeronautics and Astronautics（南京航空航天大学前沿科学技术学院）；Collaborative Innovation Center of Advanced Microstructures, Nanjing University（南京大学先进微结构协同创新中心）；Jiangsu Key Laboratory of Artificial Functional Materials, Nanjing University（南京大学江苏省人工功能材料重点实验室）
Observation of Rayleigh phonon scattering through excitation of extremely high overtones in low-loss cryogenic acoustic cavities for hybrid quantum systems
Dissipative acousto-mechanical parametric interface between high-overtone acoustics and flexural phonons
Beijing Academy of Quantum Information Sciences（北京量子信息科学研究院）；Institute of Physics, Chinese Academy of Sciences（中国科学院物理研究所）；University of Chinese Academy of Sciences（中国科学院大学）；Aalto University（阿尔托大学）；Tsinghua University（清华大学）
Loss Mechanisms in High-coherence Multimode Mechanical Resonators Coupled to Superconducting Circuits
ETH Zurich（苏黎世联邦理工学院）；University of Innsbruck（因斯布鲁克大学）；Institute for Quantum Optics and Quantum Information, Austrian Academy of Sciences（奥地利科学院量子光学与量子信息研究所）；University of Sao Paulo（圣保罗大学）
