Phononic bath engineering of a superconducting qubit

Phonons, the ubiquitous quanta of vibrational energy, play a vital role in the performance of quantum technologies. Conversely, unintended coupling to phonons degrades qubit performance and can lead to correlated errors in superconducting qubit systems. Regardless of whether phonons play an enabling or deleterious role, they do not typically admit control over their spectral properties, nor the possibility of engineering their dissipation to be used as a resource. Here we show that coupling a superconducting qubit to a bath of piezoelectric surface acoustic wave phonons enables a novel platform for investigating open quantum systems. By shaping the loss spectrum of the qubit via the bath of lossy surface phonons, we demonstrate preparation and dynamical stabilization of superposition states through the combined effects of drive and dissipation. These experiments highlight the versatility of engineered phononic dissipation and advance the understanding of mechanical losses in superconducting qubit systems. Hybrid quantum acoustic systems integrating qubits with phonons offer a novel platform for investigating open quantum systems. Kitzman et al. report control of superposition states of a transmon qubit under the effect of drive and dissipation by engineering its coupling to a bath of surface acoustic wave phonons.

Automated summary

This article investigates a new platform for studying open quantum systems by coupling superconducting qubits with piezoelectric surface acoustic wave phonons. By shaping the loss spectrum of the qubit through the bath of lossy surface phonons, the researchers demonstrate the preparation and dynamical stabilization of superposition states through drive and dissipation. These experiments highlight the versatility of engineered phononic dissipation and advance the understanding of mechanical losses in superconducting qubit systems.