Strain Coupling Between Diamond Resonators and NV Spins

Short answer: Researchers have shown that the spin of a nitrogen-vacancy (NV) centre in diamond can be driven by mechanical strain from a vibrating diamond structure. Two 2013 and 2014 papers report this coupling, including a strain sensitivity of 3 x 10^-6 per root hertz. These are laboratory demonstrations of a hybrid spin-mechanical system.

What is a hybrid spin-mechanical system?

The 2014 Nature Communications abstract explains that hybrid quantum systems are central to emerging quantum technologies, including quantum information science and quantum-assisted sensing. High-quality single-crystal diamond resonators have drawn interest in a system where nitrogen-vacancy centre spins interact with the resonant phonon modes of a macroscopic mechanical resonator through crystal strain. The authors say that before their work the NV spin-strain interaction had not been well characterized.

What did the first experiments show?

A 2013 Physical Review Letters paper from a group at Cornell University, with authors E. R. MacQuarrie, T. A. Gosavi, N. R. Jungwirth, S. A. Bhave and G. D. Fuchs, demonstrated direct coupling between phonons and NV centre spins by driving spin transitions with mechanically generated harmonic strain at room temperature. The amplitude of the mechanically driven spin signal varies with the spatial periodicity of the stress standing wave in the diamond substrate, which the authors take as verification that the spins are driven mechanically. They suggest the interaction could offer quantum spin control of magnetically forbidden transitions, enhance NV-based quantum metrology, and open direct transitions between all spin-1 states of the NV centre.

The 2014 Nature Communications paper demonstrates dynamic, strain-mediated coupling between the motion of a diamond cantilever and the spin of an embedded NV centre. Using quantum control of the spin, the authors quantitatively characterize the axial and transverse strain sensitivities of the NV ground-state spin. They then demonstrate spin-based strain imaging with a strain sensitivity of 3 x 10^-6 strain per root hertz. Finally, they argue the spin-resonator system could enable coherent spin-phonon interactions in the quantum regime, which is a prospect and not something the abstract says was shown.

What about the newer paper?

A 2025 article in APL Quantum is titled "Tuning strain coupling between diamond oscillators and NV centers via interference of two mechanical modes." The page this post checked returned no readable abstract, so nothing is claimed here about its method or results beyond its title.

How to read these results

All of these are small experiments on individual devices. The 2013 result was at room temperature, and the 2014 sensitivity figure is the authors' own. The abstracts do not report a fully quantum-coherent spin-phonon interaction. This post is based on abstracts and visible summary text, and full papers were not checked. It makes no claim about products or deployed sensors.

FAQ

How does strain affect an NV centre?

The 2014 authors characterized axial and transverse strain sensitivities of the NV ground-state spin and used them for spin-based strain imaging.

Was this shown at room temperature?

The 2013 Physical Review Letters paper drove spin transitions with mechanically generated strain at room temperature.

What strain sensitivity was reported?

3 x 10^-6 strain per root hertz, according to the 2014 Nature Communications abstract.

Is coherent spin-phonon coupling demonstrated?

The 2014 authors say the system could enable it in the quantum regime. The abstracts do not report it as achieved.