Floquet analysis of coherence in periodically driven diamond NV ensemble systems
Abstract
High-density nitrogen-vacancy (NV) ensembles are promising platforms for solid-state quantum sensing, but their performance is limited by dipolar interactions and inhomogeneous dephasing. Periodic decoupling sequences such as Waugh-Huber-Haeberlen (WAHUHA) can extend the observed stroboscopic decay time, but a longer fitted lifetime does not necessarily imply improved magnetic-field sensitivity. Here, we experimentally demonstrate this disconnect experimentally. WAHUHA increases the fitted stroboscopic decay time from T2* of 0.9 μs to T2,eff* of 31 μs, while producing little improvement in dc magnetic-field sensitivity. Using detuning-resolved stroboscopic spectroscopy and finite-pulse Floquet analysis, we show that the long-lived signal arises from phase wrapping and quasienergy branch folding of the one-cycle unitary. These effects reshape the stroboscopic spectrum, and the experimentally relevant folded branches exhibit a reduced local detuning-to-phase transduction slope, dΦ/dΔ, which governs the dc magnetic-field response. Our results demonstrate that, under periodic driving, an extended effective dephasing time does not necessarily translate into enhanced dc sensitivity and establish finite pulse Floquet analysis as a practical framework for evaluating coherence in spin ensembles.
Related
- Floquet-ADAPT-VQE: A Quantum Algorithm to Simulate Non-Equilibrium Physics in Periodically Driven Systems
- Semiclassical spin-bath calculation of the nitrogen-isotope effect on NV- ensemble coherence in diamond
- Engineering and Probing a One-Dimensional Dipolar Spin Ensemble in Diamond
- Theoretical study of nitrogen-vacancy spin coherence enhanced by vacancy aggregation in diamond using cluster-correlation expansion
- The use of Peres lattices in periodically driven systems
BibTeX
@misc{nguyen2026floquet,
title = {{Floquet analysis of coherence in periodically driven diamond NV ensemble systems}},
author = {Cuong M. Nguyen and Uijin Ko and Seong-Joo Lee and Hyeonsu Kim and Hosung Seo and Sangwon Oh},
howpublished = {arXiv},
year = {2026},
month = sep,
doi = {10.48550/arxiv.2606.10452},
eprint = {2606.10452},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2606.10452},
note = {CC BY-NC-SA 4.0},
}
RIS
TY - UNPB
TI - Floquet analysis of coherence in periodically driven diamond NV ensemble systems
AU - Cuong M. Nguyen
AU - Uijin Ko
AU - Seong-Joo Lee
AU - Hyeonsu Kim
AU - Hosung Seo
AU - Sangwon Oh
PY - 2026
DA - 2026/09/17
PB - arXiv
DO - 10.48550/arxiv.2606.10452
UR - https://arxiv.org/abs/2606.10452
AB - High-density nitrogen-vacancy (NV) ensembles are promising platforms for solid-state quantum sensing, but their performance is limited by dipolar interactions and inhomogeneous dephasing. Periodic decoupling sequences such as Waugh-Huber-Haeberlen (WAHUHA) can extend the observed stroboscopic decay time, but a longer fitted lifetime does not necessarily imply improved magnetic-field sensitivity. Here, we experimentally demonstrate this disconnect experimentally. WAHUHA increases the fitted stroboscopic decay time from T_2^* of 0.9 μs to T_2,eff^* of 31 μs, while producing little improvement in dc magnetic-field sensitivity. Using detuning-resolved stroboscopic spectroscopy and finite-pulse Floquet analysis, we show that the long-lived signal arises from phase wrapping and quasienergy branch folding of the one-cycle unitary. These effects reshape the stroboscopic spectrum, and the experimentally relevant folded branches exhibit a reduced local detuning-to-phase transduction slope, dΦ/dΔ, which governs the dc magnetic-field response. Our results demonstrate that, under periodic driving, an extended effective dephasing time does not necessarily translate into enhanced dc sensitivity and establish finite pulse Floquet analysis as a practical framework for evaluating coherence in spin ensembles.
ER -