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Recently, the scientific research team of the School of Communication and Information Engineering of the Southern University of Posts and Posts has made a major breakthrough in the development of the diamond NV color center quantum magnetometer. For the first time, the team used the diamond NV color center solid-state quantum system to achieve quantum precision measurements in the magnetic field range of 0.01 T – 1.5 T.Diamond NV color center quantum magnetometer
Diamond NV (nitrogen vacancy) color center quantum magnetometer is an ultra-precision measurement tool, a precision ruler of magnetic field strength, which has been widely used in high-end magnetic materials, integrated circuit testing, medical imaging equipment research and development, physical quantity measurement, new energy carbon measurement and other fields, and has been applied by Huawei, HiSilicon, ZTE, State Grid, China Iron and Steel Research Institute, metrology institutions and other enterprises.
This innovation has the significant advantages of high spatial resolution and wide measuring range, and has important application value in cutting-edge applications such as industrial magnetic measurement, medical imaging equipment research and development, and integrated circuit testing. This innovative achievement marks a solid step in the field of quantum magnetic measurement in China, and in the era of quantization of measurement, it is expected to provide more convenient services for advanced manufacturing industry. This technology provides a common support technology for the quantitative microscopic measurement and analysis of high-end permanent magnets, which is of great significance for improving the R&D and manufacturing capabilities of high-end magnetic materials in China.
It is worth mentioning that the School of Communication and Information Engineering of Nanjing University of Posts and Telecommunications stood out among 319 entries in the 14th Challenge Cup College Student Innovation and Entrepreneurship Plan Competition in Jiangsu Province after fierce competition, and three projects won the gold medal of the competition.
The Chinese Institute of Metrology is one of the authoritative metrology institutions in China and has a wide influence in the metrology industry. The diamond NV color center quantum magnetometer strictly follows the JJF1832-2020 magnetometer calibration specification, and has been strictly calibrated by the Chinese Institute of Metrology to ensure the accuracy of the measurement results. Calibrated with PT2025, the magnetometer has an accuracy of better than 13 ppm in the 1.0–1.5T range, a level of accuracy that has been reported for the first time internationally and is comparable to the Metrolab PT series NMR magnetometers, the gold standard in magnetic field metrology. Unlike the PT series NMR magnetometers, which require the replacement of three probes with different ranges in the range of 0.05 T to 1.5 T, the diamond NV color center quantum magnetometer can cover a continuous magnetic field range of 0.01 T to 1.5 T with a single probe, which greatly simplifies the measurement process and improves efficiency, extending the measurement range of the NMR magnetometer.
The spatial resolution of the diamond NV color center quantum magnetometer reaches the micron size, while the PT2025 nuclear magnetic resonance magnetometer probe of the world-renowned Swiss Metrolab company has a millimeter scale, and has strict requirements for the gradient of the magnetic field to be measured, usually less than 1000 ppm/cm. The diamond NV color center quantum magnetometer is expected to solve the problem of lack of quantum metrology technology for large magnetic field gradients due to the fact that the magnetic field-sensitive core material is only micron in size. The team has successfully achieved a self-traceable microscopic measurement of the magnetic field strength on the surface of a single cylindrical permanent magnet.
Microscopic self-traceable measurement of magnetic field on the surface of high-end samarium cobalt permanent magnets
The quantum precision measurement team of SUPT has been engaged in the research of quantum precision measurement technology methodology and the development of experimental systems for a long time, exploring the application of quantum precision measurement in cutting-edge fields such as chip testing, microscopic testing and characterization of magnetic materials, and magnetic field measurement. This achievement is one of the decades of research accumulation of the research team of the Peter Grünberg Research Center of Nanjing University of Posts and Telecommunications, and the achievement is supported by the National Key R&D Program and the Technical Field Fund of the Basic Strengthening Program.
