As one of the core development directions of quantum technology, quantum sensing employs the intrinsic property of microscopic particles to realize the measurement of physical quantities, with the characteristics of high sensitivity, high stability and high accuracy. Compared with the traditional traceability method, applying the quantum effect to reproduce the value, the traceability link is shorter; the speed is faster, and the measurement result is more accurate and stable. This paper focuses on the precision current measurement based on quantum sensing. Aiming at the giant magneto-resistance (GMR) effect, superconducting quantum interference device (SQUID) and diamond nitrogen-vacancy (NV) color center, the measurement principle, key technology, performance index and application field are expounded. Fully develop the intrinsic property of quantum; the quantum sensing performance index may exceed the classical measurement limit, which has great application potential and broad prospect in the field of current measurement. It is worthy of attention and in-depth research.
As one of the core development directions of quantum technology, quantum sensing employs the intrinsic property of microscopic particles to realize the measurement of physical quantities, with the characteristics of high sensitivity, high stability and high accuracy. Compared with the traditional traceability method, applying the quantum effect to reproduce the value, the traceability link is shorter; the speed is faster, and the measurement result is more accurate and stable. This paper focuses on the precision current measurement based on quantum sensing. Aiming at the giant magneto-resistance (GMR) effect, superconducting quantum interference device (SQUID) and diamond nitrogen-vacancy (NV) color center, the measurement principle, key technology, performance index and application field are expounded. Fully develop the intrinsic property of quantum; the quantum sensing performance index may exceed the classical measurement limit, which has great application potential and broad prospect in the field of current measurement. It is worthy of attention and in-depth research.
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.
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.
Quantum sensing is a paradigm shift in measurement science. It uses the intrinsic quantum properties of particles and their wave functions, such as superposition, entanglement, and coherence, to achieve unparalleled sensitivity, precision, and miniaturization. This paper provides a practical engineering perspective on quantum sensing, linking foundational quantum principles to real-world applications. It reviews key enabling technologies, such as single-photon detectors, which can detect individual photons with high efficiency and low noise; nitrogen vacancy (NV) centers in diamonds, which sense nanoscale magnetic and electric fields at room temperature; and Rydberg atoms, which detect precise electromagnetic fields using optical techniques. Additionally, we examine the integration of quantum sensing approaches with optical fiber systems, high-lighting advances in distributed sensing capabilities enabled by quantum detectors. The discussion emphasizes the advantages of quantum measurement techniques over classical methods. Finally, it outlines the emerging domain of quantum sensing applications and the ongoing miniaturization and cost reduction of quantum devices, demonstrating their potential to transform multiple scientific and industrial fields.
Quantum sensors and metrology harness quantum phenomena—such as superposition, entanglement, and squeezing—to achieve precision measurements beyond classical limits. This review presents an overview of the fundamental principles underlying quantum sensing, including quantum coherence, entanglement-assisted measurement, and quantum-enhanced interferometry. Various quantum sensor platforms are discussed, including atomic clocks, nitrogen-vacancy (NV) center magnetometers, superconducting quantum interference devices (SQUIDs), optomechanical sensors, and trapped-ion systems. We explore their operational mechanisms, performance metrics, and technological implementations. Comparative analyses highlight sensitivity, spatial resolution, bandwidth, and environmental robustness. Advances in materials, control techniques, and hybrid architectures are examined, and emerging applications in navigation, geophysics, medical imaging, and fundamental physics are reviewed. Finally, future prospects for scalable and robust quantum metrology are discussed.
Background: High-precision sensing is vital for modern technology, yet conventional sensors are fundamentally constrained by classical noise limits. Quantum sensing leverages principles of quantum mechanics, such as superposition and entanglement, to overcome these barriers, offering unprecedented sensitivity. This review comprehensively analyzes the current state of quantum sensor technology, focusing on its underlying physical principles, emerging applications, and the pathway toward industrial maturation.Methods: We synthesize findings from key research areas, detailing the foundational quantum systems like Nitrogen-Vacancy (NV) centers in diamond and advanced optical techniques. The paper reviews the theoretical methods used to achieve sub-shot-noise performance and discusses the system-level engineering challenges necessary for practical deployment, particularly concerning microwave control and optical readout. We also assess the current landscape of standardization efforts for quantum technologies.Results: Significant breakthroughs are highlighted in both biomedical and environmental sensing. Applications range from tracking cellular redox-status using electron-paramagnetic resonance to ultra-sensitive salinity measurements. The analysis confirms that quantum sensing provides superior resolution compared to classical counterparts, unlocking new capabilities in in-vivo and real-time monitoring.Discussion: While offering transformative potential, widespread adoption faces hurdles, including the maintenance of quantum coherence in ambient environments and the high cost and complexity of current instrumentation. Future efforts must focus on miniaturization, integration with classical systems, and standardized fabrication protocols. Quantum sensing represents the next-generation technological paradigm for metrology.
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.