Harvard Researchers Use Vibrations To Boost Qubit Stability

Eliza Cornell, a recent Ph. D. graduate from the Lončar lab and now at Boston University, led experiments demonstrating a new method for extending the life of quantum information using mechanical vibrations. Researchers at the Harvard John A. Paulson School of Engineering and Applied Sciences harnessed phonons, particles of sound, to protect the spin of an electron associated with an impurity in diamond, a promising quantum memory.

Phonon wavelengths are significantly shorter than those of light, enabling smaller devices and tighter integration for future quantum networks. “We want the spin to have strong interaction with phonons, and we want the spin to have a long coherence time,” Cornell said.

“Dressed” Qubit States Extend Silicon-Vacancy Coherence Times

A threefold extension of silicon-vacancy spin coherence time demonstrates a new path toward stable quantum information storage, according to a team at the Harvard John A. This approach bypasses limitations of traditional microwave pulse methods when working with qubits housed within phononic cavities. The team’s innovation centers on utilizing phonons, particles of sound, not only as carriers of quantum information between qubit nodes but also as a means of protecting that information.