All-fiber quantum relaxometry for biochemical sensing based on diamond NV centers
At a Glance
Section titled āAt a Glanceā| Metadata | Details |
|---|---|
| Publication Date | 2024-07-24 |
| Journal | Optics Express |
| Authors | Hongda Chen, Yunhan Luo, Xiaoling Luo, Xue Chen, Yuxin Li |
| Institutions | Ji Hua Laboratory |
| Citations | 5 |
Abstract
Section titled āAbstractāThe longitudinal relaxation time (termed as T 1 ) of nitrogen-vacancy (NV) centers in nanodiamonds can be affected by surface electric or magnetic noise, which has been exploited to develop cutting-edge quantum relaxometry for biochemical sensing. In this work, a tiny all-fiber quantum probe based on longitudinal relaxometry was developed by chemically-anchoring nanodiamonds on the surface of a cone fiber tip. The dependences of T 1 on surface electric and magnetic noise were discussed in theories first and then experimentally demonstrated in varied pH and Gd 3+ concentration solutions, respectively. Because of NV centers being subject to enhanced coupling from surface noise, T 1 reduced from 290 to 245 Āµs when pH changed from 3 to 9 and reduced to 220 Āµs when Gd 3+ concentration increased to 10 mM, agreeing well with theoretical results. Based on these, the Gd 3+ -tagged-biotin and streptavidin model was designed and implemented on the all-fiber probe, and results demonstrated the detection of biotin with a limit of 168 nM and good specificity. This paper opens a new way to develop an all-fiber quantum probe by exploiting the unique electrical spin properties of NV centers, and the probe shows great potential for biological detection with high sensitivity and specificity.