Overview
We explore new approaches for quantum control phonons with exceptionally long coherence times for use in quantum systems. Combining advanced materials characterization with novel cryogenic phonon spectroscopy techniques, we identify the microscopic origins of dissipation and noise that limit phonon coherence in crystalline media. Using these materials studies to guide the design of ultra-coherent mechanical systems, we devise new strategies to harness them for quantum memory and quantum transduction applications.
Our team has pioneered the development micro-fabricated high-overtone bulk acoustic resonators (uHBARs)—a versatile and scalable platform for creating exceptionally long-lived mechanical modes at gigahertz frequencies. These devices have demonstrated record-setting phonon coherence times, establishing new performance bounds for mechanical systems in the solid state. Their compact footprint and compatibility with optical and microwave coupling make them ideal for integration into hybrid quantum circuits.
To access and control such long phonons at the quantum level, we leverage tools from cavity optomechanics and circuit quantum electrodynamics (cQED), enabling coherent coupling between photons, phonons, and superconducting qubits. These hybrid systems allow for phonon-based quantum memories, microwave-to-optical transduction, and basic tests of quantum behavior in macroscopic mechanical systems. Through this work, build a foundation for scalable, noise-resilient quantum devices that integrate acoustic, optical, and electronic degrees of freedom.
