Robustness improvement of a nitrogen-vacancy magnetometer by a double driving method

Yanjie Gao; Zhengjie Luo; Hao Guo; Huanfei Wen; Zhonghao Li; Zongmin Ma; Jun Tang; Jun Liu

doi:10.1063/5.0147094

Robustness improvement of a nitrogen-vacancy magnetometer by a double driving method

Rev Sci Instrum. 2023 Jun 1;94(6):065015. doi: 10.1063/5.0147094.

Authors

Yanjie Gao¹, Zhengjie Luo¹, Hao Guo¹, Huanfei Wen¹, Zhonghao Li¹, Zongmin Ma¹, Jun Tang¹, Jun Liu¹

Affiliation

¹ State Key Laboratory of Dynamic Measurement Technology, Shanxi Province Key Laboratory of Quantum Sensing and Precision Measurement, North University of China, Taiyuan 030051, China.

PMID: 37862530
DOI: 10.1063/5.0147094

Abstract

The nitrogen vacancy (NV) color center in diamonds is an electron spin that can measure magnetic fields with high sensitivity and resolution. Furthermore, the robustness of an NV-based quantum system should be improved for further application in other sensing methods and in the exploration of basic physics. In this work, the robustness of an NV magnetometer is improved by the double driving method. The sensitivity of the NV magnetometer was improved 2.1 times by strengthening the pumping power from 100 to 600 mW. In this process, thermal drift was introduced, which affects the measurement accuracy. The temperature drift of a diamond matrix was measured using an infrared camera, and the temperature change of a diamond host drifted to ∼80 K under high laser and microwave power. To address the drift of temperature owing to sensitivity improvement by pumping enhancement, the double driving method was introduced, to suppress the drift of the resonance frequency, to improve the robustness of a continuous-wave NV magnetometer. The magnetic noise density was improved from 10 to 1.2 nT/Hz1/2. This study checked the source of temperature noise in the process of measuring with the NV color centers and proposes a double driving measurement method to track the resonant frequency change due to environmental temperature drift and improve sensitivity. The findings of this study are useful in applying complex pulse protocols in high-level sensing applications based on solid-state spin.