Nature Physics, Published online: 30 July 2026; doi:10.1038/s41567-026-03321-4
Using Brillouin-based phonon spectroscopy, surface interactions have been identified as the dominant source of phonon decoherence in crystalline media. When these interactions are reduced through chemical mechanical polishing, high-frequency bulk acoustic wave oscillators can be realized with record Q-factors and coherence times, suitable for use as long-lived solid-state quantum memories.
