Gate Synthesis in Dephasing-Limited Nitrogen-Vacancy Ensembles
Abstract
Ensemble nitrogen-vacancy (NV) centers are widely used for quantum sensing and magnetometry, where performance depends on the accurate implementation of microwave pulse sequences. In these systems, inhomogeneous broadening and short coherence times limit reliable multi-pulse control, while hardware imperfections and off-resonant excitation distort implemented rotations, making direct calibration of arbitrary gates tedious. To address this, we implement a control framework with a ZXZXZ gate decomposition which uses fixed-angle, phase-parameterized pulses, enabling universal single-qubit control from a single calibrated $ π/2$ primitive (Xπ/2) along with virtual Z operations. We compare a standard pulse with a composite pulse designed for high-power operation in a regime where the Rabi frequency is comparable to the hyperfine splitting, leading to non-uniform evolution across hyperfine levels. Using pre-determined combinations of π/2 pulse sequences, we observe that standard pulses rapidly deviate from ideal behavior under repeated application, while the composite pulse suppresses this error accumulation by more than 70% for longer sequences despite its longer duration. In contrast, randomized benchmarking yields similar decay factors for both implementations, highlighting its limited sensitivity to coherent control errors. These results establish a practical route to robust control in short-coherence ensemble systems and emphasize the importance of pulse-level characterization.
Related
- Thermometry in Near-Degenerate Nitrogen-Vacancy Ensembles Enabled by Bright-Dark-State Mixing
- Magnonic cavity-enhanced quantum magnetometry with nitrogen-vacancy centre ensembles
- All-fiber quantum current transformer based on nitrogen-vacancy centers
- Model-Based Fast Calibration for a Nitrogen Vacancy Center QPU
- Exact Breit-Rabi formulae for the nitrogen-vacancy center in diamond
BibTeX
@misc{chakravarty2026gate,
title = {{Gate Synthesis in Dephasing-Limited Nitrogen-Vacancy Ensembles}},
author = {Ankita Chakravarty and Arnaud Carignan-Dugas and Eva Dupont-Ferrier and Yves Bérubé-Lauzière},
howpublished = {arXiv},
year = {2026},
month = sep,
doi = {10.48550/arxiv.2609.31913},
eprint = {2609.31913},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2609.31913},
note = {CC BY-SA 4.0},
}
RIS
TY - UNPB
TI - Gate Synthesis in Dephasing-Limited Nitrogen-Vacancy Ensembles
AU - Ankita Chakravarty
AU - Arnaud Carignan-Dugas
AU - Eva Dupont-Ferrier
AU - Yves Bérubé-Lauzière
PY - 2026
DA - 2026/09/25
PB - arXiv
DO - 10.48550/arxiv.2609.31913
UR - https://arxiv.org/abs/2609.31913
AB - Ensemble nitrogen-vacancy (NV) centers are widely used for quantum sensing and magnetometry, where performance depends on the accurate implementation of microwave pulse sequences. In these systems, inhomogeneous broadening and short coherence times limit reliable multi-pulse control, while hardware imperfections and off-resonant excitation distort implemented rotations, making direct calibration of arbitrary gates tedious. To address this, we implement a control framework with a ZXZXZ gate decomposition which uses fixed-angle, phase-parameterized pulses, enabling universal single-qubit control from a single calibrated $ π/2$ primitive (X_π/2) along with virtual Z operations. We compare a standard pulse with a composite pulse designed for high-power operation in a regime where the Rabi frequency is comparable to the hyperfine splitting, leading to non-uniform evolution across hyperfine levels. Using pre-determined combinations of π/2 pulse sequences, we observe that standard pulses rapidly deviate from ideal behavior under repeated application, while the composite pulse suppresses this error accumulation by more than 70% for longer sequences despite its longer duration. In contrast, randomized benchmarking yields similar decay factors for both implementations, highlighting its limited sensitivity to coherent control errors. These results establish a practical route to robust control in short-coherence ensemble systems and emphasize the importance of pulse-level characterization.
ER -