A Highly Integrated, High-Sensitivity Magnetometer Based on Diamond Nitrogen-Vacancy Centers

Solid-state quantum sensing technology based on diamond nitrogen-vacancy (NV) centers has become a powerful tool for magnetic field detection and has great promise for applications. However, the environmental requirements and bulky instrumentation associated with optically detected magnetic resonance (ODMR) measurement methods need to be avoided in practical applications, and the magnetometric sensitivity of the system needs to be further improved. In this article, we propose a high-precision integrated portable magnetometer (HIPM) with a volume limit of 150 cm3. The system integrates larger equipment and bulky instruments, which greatly improves the integration of the system, and also designs the corresponding signal conditioning circuit (SCC) to process the fluorescence signal, which ensures the integration of the system and makes the sensitivity improved. In addition, according to our test comparison, the interference between microwave (MW) signal and SCC is effectively and strongly shielded during the experiment, which is a guideline for the future integration design. Subsequently, we verified that the magnetic sensitivity of the system is about 16.03 nT/Hz $^{{1}/{2}}$ . This new sensing system has a high level of integration and possesses good magnetometric sensitivity.