ÖPG-CMD Joint Meeting 2026

Comprehensive First-Principles Description of Spin–Phonon Coupling in Nitrogen–Vacancy Diamond

Sep 24, 2026, 5:15 PM

15m

HS 12.11 (University of Graz)

3) Contributed talk M24 - Computational Frontiers in Structure Prediction, Lattice Dynamics, and Electron-Phonon Coupling Mini-Colloquium

Speaker

Dr Zhishuo Huang (Electrical Engineering and Computer Science, Technische Universität Berlin, 13355 Berlin, Germany)

Description

The nitrogen–vacancy (NV) centre in diamond is a leading platform for nanoscale quantum sensing of magnetic fields, temperature, and strain. Sensing sensitivity is fundamentally bounded by the spin–lattice relaxation time T$_1$, making its accurate prediction essential for optimizing quantum sensor performance. Cambria et al.[1] advanced this goal with an ab initio framework reproducing NV$^–$ relaxation rates from 9–474 K and identifying second-order spin–phonon processes as the dominant Raman mechanism. However, their $\Gamma$-point Brillouin-zone sampling in a finite supercell leaves the continuous phonon dispersion unresolved, likely causing the reported eightfold underestimation of the single-quantum relaxation rate. More broadly, no existing treatment consistently couples correlated wavefunction methods for the defect’s multi-reference electronic structure with rigorous periodic lattice dynamics for the host crystal[2].
We present a framework that closes this gap. Quantum chemistry calculations on embedded NV clusters yield spin-state-resolved energies and spin–orbit coupling derivatives with high-level electron correlation, while density functional perturbation theory within Quantum ESPRESSO[3] provides the full phonon dispersion across the Brillouin zone. These are connected via Wannier-interpolated electron–phonon matrix elements (EPW)[4] on dense wavevector grids. The resulting spin–phonon coupling Hamiltonian enables parameter-free evaluation of T$_1$, resolving direct, Raman, and Orbach processes over the full temperature range, and identifies which phonon branches and Brillouin-zone regions dominate relaxation at each temperature. This provides a microscopic basis for phonon engineering strategies transferable to other solid-state spin defect platforms, opening pathways for enhancing T$_1$.
References
[1] M.C. Cambria et al., PRL 130, 256903 (2023).
[2] M. Onizhuk, G. Galli, RMP 97, 021001 (2025).
[3] P. Giannozzi et al., JPCM 21, 395502 (2009).
[4] S. Poncé et al., CPC 209, 116 (2016).