A Portable Application Type Magnetometer Based on Diamond NV Centers

In recent years, there has been significant progress in the development of quantum precision measurement techniques. One particularly promising application is the use of the magnetometer based on diamond nitrogen vacancy (NV). However, to make this magnetometer more practical and flexible, it must be considered to avoid all the large instrumentation it involves and ensure a good magnetic sensitivity. In this article, we propose a high-precision portable application magnetometer (HPAM) that integrates all the equipment in the optical detection of magnetic resonance (ODMR) and limits the overall volume to about 190 cm3. We have also used a signal conditioning module (SCM) to process the fluorescence signal and enhance the sensitivity of the system. In addition, we separate the optical probe part from the back-end circuit part to well avoid interference between them; in the back-end part, we use 4G wireless data transmission and are equipped with a global positioning system (GPS) for remote magnetometry, which is a guideline for future practical integration design. Finally, we verified that the magnetic sensitivity of the system is about 4.22 nT/Hz $^{{1}/{2}}$ at 100 Hz and the total power consumption is 2.225 W. This new sensing system integrates all devices and has a good magnetic sensitivity.