AIBRIEF
A Harvard team used continuous mechanical vibrations to shield a diamond based qubit, extending its coherence time roughly threefold in a new Nature Physics paper.
Vibrations were once the enemy of quantum memory. A Harvard team has turned them into a continuous protective bath, keeping a single quantum bit's information intact roughly three times longer than before, according to a Nature Physics paper published in September 2026.
A quantum bit, or qubit, is the basic unit of a quantum computer, analogous to a bit in a classical machine. The Harvard qubit stores information in the spin of an electron inside a defect in a diamond crystal, but it loses that information quickly to noise. The time it can hold that fragile state before noise scrambles it is called its coherence time.
The team built a phononic cavity, a structure that traps tiny packets of mechanical vibration, essentially particles of sound, around the diamond qubit. By tuning it to resonate continuously with the electron spin, they locked the qubit into a "dressed state" protected from drift, the Harvard John A. Paulson School of Engineering and Applied Sciences explained. The approach roughly tripled coherence time.
The result, summarized in ScienceDaily, points to sound rather than light as a future carrier of quantum information between chips. Phonons have shorter wavelengths than photons at the same frequency, which allows denser on-chip components, and they interact with both solid-state spins and electromagnetic fields. The work was led by Eliza Cornell and Zhujing Xu in the lab of Marko Lončar, the Tiantsai Lin Professor of Electrical Engineering at Harvard SEAS; a related arXiv preprint provides additional detail.
The advance is still lab-scale. Chip-scale quantum networks built on phonons remain a goal, not a delivered system.