IEEE International Conference on Internet of Things (iThings) and IEEE Green Computing and Communications (GreenCom) and IEEE Cyber, Physical and Social Computing (CPSCom) and IEEE Smart Data (SmartData)
High Accuracy Current Comparator Technology based on Solid-state Quantum Precision Measurement
Tianfu Huang, Tongyao Lin, Hanbin Huang, Xiaofei Li, Qi Nie, Han Wang
The existing high-level current ratio standard devices are all based on the principle of magnetic modulation-type comparators, with uncertainties reaching the order of 10^-6, making it difficult to further improve accuracy. This article addresses one of the main reasons limiting the improvement of accuracy in current comparators, which is the error caused by insufficient sensitivity of the Ampere balance device. Firstly, it initiates the design of a shield structure based on superconductors to reduce the impact of magnetic leakage. Secondly, it investigates a solid-state spin measurement method using diamond NV (Negatively Nitrogen Vacancy, NV) color centers. This method is based on a fixed microwave frequency and measures changes in the optically detected magnetic resonance spectrum to achieve magnetic field measurement. Through an analysis of the overall system error, theoretical limits are presented for a high-accuracy current comparator based on superconductors and solid-state quantum precision measurement.
The existing high-level current ratio standard devices are all based on the principle of magnetic modulation-type comparators, with uncertainties reaching the order of 10^-6, making it difficult to further improve accuracy. This article addresses one of the main reasons limiting the improvement of accuracy in current comparators, which is the error caused by insufficient sensitivity of the Ampere balance device. Firstly, it initiates the design of a shield structure based on superconductors to reduce the impact of magnetic leakage. Secondly, it investigates a solid-state spin measurement method using diamond NV (Negatively Nitrogen Vacancy, NV) color centers. This method is based on a fixed microwave frequency and measures changes in the optically detected magnetic resonance spectrum to achieve magnetic field measurement. Through an analysis of the overall system error, theoretical limits are presented for a high-accuracy current comparator based on superconductors and solid-state quantum precision measurement.
The research focuses on the solid-state spin system of diamond NV (Negatively Charged Nitrogen Vacancy, NV) color centers, which exhibit excellent optical readout, polarization properties, and millisecond-scale coherent time. This makes it an important means to achieve quantum information processing and quantum precision measurement. Additionally, its ultrahigh sensitivity to magnetic fields provides a potential path for diamond’s high-precision current measurement. This paper investigates a reliable method in the field of direct current measurement using quantum sensing technology based on diamond NV color centers. It involves measuring the change in the optically detected magnetic resonance spectrum based on a fixed microwave frequency to achieve magnetic field measurement. Simultaneously, by utilizing the spatial distribution of magnetic sensor heads, it achieves current inversion. Finally, an experimental platform was constructed for validation. Preliminary results indicate that the linear fit error for direct current amplitude is less than 10^-7, confirming the feasibility of this technological approach and providing a potential application for diamond in measuring currents in power systems.
Negatively charged nitrogen-vacancy (NV) centers in diamond have been extensively studied as a promising high sensitivity solid-state magnetic field sensor at room temperature. However, their use for current sensing applications is limited due to the challenge of integration and miniaturization of the diamond NV sensor. Here, we demonstrate an integrated NV sensor fabricated with standard microfabrication process. The sensor device incorporated with a toroidal magnetic yoke enables a high-precision wide range direct current sensing with galvanic isolation. The performance of the diamond NV current sensor in an open loop configuration has been investigated. A current measuring range of 0 A ~ 1000 A with an uncertainty of 46 ppm are achieved. Taking advantage of dual spin resonance modulation, temperature drift is suppressed to 10 ppm/K. This configuration opens new possibilities as a robust and scalable platform for current quantum sensing technologies.
Compared to other systems, diamond NV color centers have the advantage of being small in size and can be optically polarized and read out at room temperature. At the same time, its electron spin can interact with a variety of physical quantities, thus forming a multifunctional quantum sensor. At the same time, the excitation and detection of diamond NV color centers are usually not demanding on physical conditions, which makes them highly practical. Based on this, this paper discusses the new quantum precision measurement technology based on NV color centers for ultra-high voltage (UHV) DC measurements, and analyzes the influence of the complex environmental magnetic field on the measured components of the ODMR spectrum in the UHV converter station by the NV color-centered energy level structure and the jump mechanism and the diamond NV color-centered magnetic resonance technology for optical detection. The simulation results show that the surface receiving power of the scheme is 63% of the incident light power, which realizes the high precision measurement of the current and has high sensitivity and stability.
The nitrogen-vacancy (NV) center is one of the major platforms in the evolving field of quantum technologies. The inertial surveying technology based on NV centers in diamond is a developing field with both scientific and technological importance. Quantum measurement using the solid-state spin of the NV center has demonstrated potential in both high-precision and small-volume low-cost devices. In terms of rotation measurement, the optically detected magnetic resonance has provided a perspective of the rotation measurement mechanism via the solid-state spin of the NV center. A new type of gyroscope based on the solid-state spin in diamond according to the theory has attracted considerable attention. In addition, combined with the ingenious quantum mechanics manipulation and coupling mechanism, acceleration measurement can be achieved through an efficient quantum detection technology of the NV center. This review summarizes the recent research progress in diamond-based inertial measurement, including sensitivity optimization methods for inertial measurement systems based on the NV center.
One of the promising solid-state quantum sensors is nitrogen-vacancy (NV) centers in diamond which can maintain quantum state at room temperature and under atmospheric pressure condition. Further improvement of sensitivity of the sensor is needed to detect the magnetic field from the brain. Noise reduction and simplified system are key techniques especially for the practical use of highly sensitive DC magnetic sensor. In this study, we devised a digital filtering detection method without synchronization between detector and modulator which is a similar noise reduction effect as a lock-in detection technique. We implemented the detection method for the quantum diamond sensor system with the large sensor volume [1]. The Lock-in detection technique is a typical high sensitivity technique for DC magnetic measurement. There are several different implementations of lock-in detection technique for the quantum diamond sensor including microwave modulation, magnetic field modulation, and laser modulation. However, it is a challenging task to obtain high magnetic sensitivity with a compact sensor module because these lock-in detection techniques require a lock-in amplifier or synchronization system. We devised a digital filtering detection method which is an alternative method to the lock-in detection technique. Fluorescence from the NV center is modulated by frequency modulated microwave during optical detected magnetic resonance (ODMR) measurement. The fluorescence is analyzed by digital signal processing which achieves a similar noise reduction effect as a lock-in detection technique. Our method relies on a fact that ODMR converts frequency modulation to amplitude modulation. Thus, our method is applicable not only to the NV center system but also another color center system. This work was supported by MEXT Q-LEAP, CAO PRISM, Japan. [1] Y. Masuyama et al., Rev. Sci. Instrum. 89, 125007 (2018).
In modern-day quantum metrology, quantum sensors are widely employed to detect weak magnetic fields or nanoscale signals. Quantum devices, exploiting quantum coherence, are inevitably connected to physical constants and can achieve accuracy, repeatability, and precision approaching fundamental limits. As a result, these sensors have shown utility in a wide range of research domains spanning both science and technology. A rapidly emerging quantum sensing platform employs atomic-scale defects in crystals. In particular, magnetometry using nitrogen-vacancy (NV) color centers in diamond has garnered increasing interest. NV systems possess a combination of remarkable properties, optical addressability, long coherence times, and biocompatibility. Sensors based on NV centers excel in spatial resolution and magnetic sensitivity. These diamond-based sensors promise comparable combination of high spatial resolution and magnetic sensitivity without cryogenic operation. The above properties of NV magnetometers promise increasingly integrated quantum measurement technology, as a result, they have been extensively developed with various protocols and find use in numerous applications spanning materials characterization, nuclear magnetic resonance (NMR), condensed matter physics, paleomagnetism, neuroscience and living systems biology, and industrial vector magnetometry. In this chapter, NV centers are explored for magnetic sensing in a number of contexts. In general, we introduce novel regimes for magnetic-field probes with NV ensembles. Specifically, NV centers are developed for sensitive magnetometers for applications where microwaves (MWs) are prohibitively invasive and operations need to be carried out under zero ambient magnetic field. The primary goal of our discussion is to improve the utility of these NV center-based magnetometers.