Robust Diamond Quantum Sensing in Double-Quantum 4-Ramsey Interferometry by Dual-Feedback Scheme
Abstract
We developed a highly sensitive and long-term stable diamond quantum magnetometer by integrating a dual-feedback system that compensates for common- and differential-mode frequency shifts in double-quantum (DQ) 4-Ramsey interferometry. Detecting extremely weak magnetic-field signals requires extensive signal accumulation to enhance the signal-to-noise ratio. However, deviations from the optimal operating frequencies caused by thermal drift or environmental magnetic noise severely hinder the long-term stability of such a sensing system. To overcome the limitation, we first derived analytical solutions for the signal response to common- and differential-mode detunings based on a detuning-inclusive Hamiltonian to theoretically clarify the robustness limit in DQ 4-Ramsey sensing. Guided by this theoretical model, we introduced synchronized frequency modulation and a dual-feedback scheme to independently track and compensate for these frequency shifts while maintaining an optimal magnetic-field response. The proposed method enabled stable continuous operation against temperature variations of 2.8 K. By maintaining a magnetic field sensitivity of 7.0 pT/Hz^1/2 in the frequency range of 5-100 Hz for a prolonged duration of 4 hours, we achieved an extremely low noise floor of 64 fT/Hz^1/2. During prolonged continuous sensing, the system exhibited the expected 1/T^1/2 scaling with integration time T, and prevented both the underestimation of amplitude and waveform distortion. These results establish a robust approach for long-term DQ 4-Ramsey diamond magnetometry and demonstrate its potential for detecting weak biomagnetic signals.
Related
- Enhanced dark matter quantum sensing via phase-space geometric interferometry
- Quantum Sensing for Spatial Spin Noise Mapping via Nitrogen-Vacancy Magnetic Quenching in Diamond
- Time domain non-linear quantum interferometry
- Development of quantum technologies for optical/infrared interferometry
- Induced Coherence in Quantum and Classical Interferometry: Origin and Control
BibTeX
@misc{araki2026robust,
title = {{Robust Diamond Quantum Sensing in Double-Quantum 4-Ramsey Interferometry by Dual-Feedback Scheme}},
author = {Yuta Araki and Takeharu Sekiguchi and Yuji Hatano and Naota Sekiguchi and Zehan Li and Chikara Shinei and Masashi Miyakawa and Takashi Taniguchi and Tokuyuki Teraji and Hiroshi Abe and Shinobu Onoda and Takeshi Ohshima and Mutsuko Hatano and Takayuki Iwasaki},
howpublished = {arXiv},
year = {2026},
month = oct,
doi = {10.48550/arxiv.2610.05907},
eprint = {2610.05907},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2610.05907},
}
RIS
TY - UNPB
TI - Robust Diamond Quantum Sensing in Double-Quantum 4-Ramsey Interferometry by Dual-Feedback Scheme
AU - Yuta Araki
AU - Takeharu Sekiguchi
AU - Yuji Hatano
AU - Naota Sekiguchi
AU - Zehan Li
AU - Chikara Shinei
AU - Masashi Miyakawa
AU - Takashi Taniguchi
AU - Tokuyuki Teraji
AU - Hiroshi Abe
AU - Shinobu Onoda
AU - Takeshi Ohshima
AU - Mutsuko Hatano
AU - Takayuki Iwasaki
PY - 2026
DA - 2026/10/05
PB - arXiv
DO - 10.48550/arxiv.2610.05907
UR - https://arxiv.org/abs/2610.05907
AB - We developed a highly sensitive and long-term stable diamond quantum magnetometer by integrating a dual-feedback system that compensates for common- and differential-mode frequency shifts in double-quantum (DQ) 4-Ramsey interferometry. Detecting extremely weak magnetic-field signals requires extensive signal accumulation to enhance the signal-to-noise ratio. However, deviations from the optimal operating frequencies caused by thermal drift or environmental magnetic noise severely hinder the long-term stability of such a sensing system. To overcome the limitation, we first derived analytical solutions for the signal response to common- and differential-mode detunings based on a detuning-inclusive Hamiltonian to theoretically clarify the robustness limit in DQ 4-Ramsey sensing. Guided by this theoretical model, we introduced synchronized frequency modulation and a dual-feedback scheme to independently track and compensate for these frequency shifts while maintaining an optimal magnetic-field response. The proposed method enabled stable continuous operation against temperature variations of 2.8 K. By maintaining a magnetic field sensitivity of 7.0 pT/Hz^1/2 in the frequency range of 5-100 Hz for a prolonged duration of 4 hours, we achieved an extremely low noise floor of 64 fT/Hz^1/2. During prolonged continuous sensing, the system exhibited the expected 1/T^1/2 scaling with integration time T, and prevented both the underestimation of amplitude and waveform distortion. These results establish a robust approach for long-term DQ 4-Ramsey diamond magnetometry and demonstrate its potential for detecting weak biomagnetic signals.
ER -