Hybrid diamond quantum sensor with submicrokelvin resolution under ambient conditions
At a Glance
Section titled āAt a Glanceā| Metadata | Details |
|---|---|
| Publication Date | 2024-02-27 |
| Journal | Physical Review Applied |
| Authors | Musang Gong, Jiahe Xu, Min Yu, L. Zhang, Qipeng Li |
| Institutions | East China Normal University, Huazhong University of Science and Technology |
| Citations | 2 |
Abstract
Section titled āAbstractāNitrogen-vacancy ($\mathrm{N}$-V) centers in diamond are promising quantum sensors due to their ultralong coherence time under ambient conditions and multimodal sensing capability. $\mathrm{N}$-V centers are strongly coupled to magnetic fields, leading to unprecedented sensitivity in magnetic field sensing. However, the coupling strengths between $\mathrm{N}$-V centers and other crucial parameters, such as temperature and pressure, are not as strong as that of the magnetic field, resulting in a relative low sensitivity. A previous study showed that the temperature sensitivity of a diamond quantum sensor could be largely improved by magnetic criticality enhancement. Here, we propose and demonstrate a hybrid quantum thermometer composed of bulk diamond with ensemble $\mathrm{N}$-V centers and a gadolinium magnetic flux concentrator. In addition to the magnetic criticality enhancement of gadolinium, our scheme leverages the magnetic flux concentration and ensemble $\mathrm{N}$-V centers, achieving a temperature sensitivity of about $\phantom{\rule{0.25em}{0ex}}251.5\phantom{\rule{0.25em}{0ex}}\text{nK}/\sqrt{\text{Hz}}$. Near the critical point, the spin resonance to temperature $(\mathrm{\ensuremath{\partial}}{f}_{\ifmmode\pm\else\textpm\fi{}}/\mathrm{\ensuremath{\partial}}T)$ reached $57.3\phantom{\rule{0.25em}{0ex}}\text{MHz}/\text{K}$ under an external magnetic field of 1.213 G, which is about 774 times enhanced compared with that of bare $\mathrm{N}$-V centers. The submicrokelvin temperature resolution of our hybrid thermometer can be used in the calibration of a reference point of temperature, integrated marine environmental surveys, laser-frequency stabilization, aerospace high-stability temperature-control systems, and many other practical applications on a macroscopic scale.