Using a diamond’s center to measure magnetic fields

Vector magnetometers dynamically reconstruct the vector magnetic fields for use in applications such as magnetic navigation, magnetic anomaly detection, and geological mapping. Tong et al. developed a customized control and readout device capable of performing real-time magnetic vector measurements.

While various vector magnetometers are available, a single sensor can only measure the magnetic field projection along a specified axis resulting in the need for multiple sensors to perform field measurements. Multiple sensors inherently have manufacturing and installation imperfections that lead to increased error in the resulting data.

The researchers used the nitrogen-vacancy centers that occur in diamonds to implement magnetic field sensors. Because of their four crystallographic axes, the areas of nitrogen-vacancy can be used simultaneously to measure magnetic field direction.

“The realization of real-time measurement of magnetic vectors uses diamond as a magnetic sensor,” said author Xi Qin. “This design is now the fastest solution for realizing vector magnetic field measurements.”

The instrument’s architecture consists of eight independent lock-in modules, a four-channel proportional integral derivative controller, a vector filed reconstruction module, a reference generator, a noise suppression module, and a field-programmable-gate-array chip. Using this customized device and readout, the vector magnetic field can be measured and reconstructed in real-time.

The research equipment has a promising future in practical applications requiring high performance, immediate vector magnetic field sensing.

“This device will contribute to the development of nitrogen-vacancy-based vector magnetometers in real-time magnetic sensing and imaging applications,” said Qin.

Source: “A customized control and readout device for vector magnetometers based on nitrogen-vacancy centers,” by Yu Tong, Wenzhe Zhang, Xi Qin, Yijin Xie, Xing Rong, and Jiangfeng Du, Review of Scientific Instruments (2023). The article can be accessed at https://doi.org/10.1063/5.0132545 .