Diamond nitrogen-vacancy (NV) centers have attracted extensive research interest for quantum sensing applications across various physical domains, owing to their prolonged coherence times and the capability of optical readout at room temperature, which offers a promising technical pathway for detecting fast-responding and transient signals in emerging power systems. This work presents a quantum sensing device based on the Zeeman and Stark effects of NV centers, designed for power system measurement applications, with a rated voltage of 10kV and a rated current of 1kA, enabling simultaneous voltage and current sensing. The device achieves a measurement accuracy of 0.69% under the rated voltage of 10 kV and +0.23% under the rated current of 1 kA, verifying the feasibility of employing quantum sensing based on NV centers for simultaneous voltage and power measurements in power systems.
Diamond nitrogen-vacancy (NV) centers have attracted extensive research interest for quantum sensing applications across various physical domains, owing to their prolonged coherence times and the capability of optical readout at room temperature, which offers a promising technical pathway for detecting fast-responding and transient signals in emerging power systems. This work presents a quantum sensing device based on the Zeeman and Stark effects of NV centers, designed for power system measurement applications, with a rated voltage of 10kV and a rated current of 1kA, enabling simultaneous voltage and current sensing. The device achieves a measurement accuracy of 0.69% under the rated voltage of 10 kV and +0.23% under the rated current of 1 kA, verifying the feasibility of employing quantum sensing based on NV centers for simultaneous voltage and power measurements in power systems.
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.
High-voltage substations impose stringent requirements on current measurement, demanding simultaneously high electrical insulation and stable, high-precision performance. Here we propose and experimentally validate an all-fiber quantum current transformer based on nitrogen-vacancy (NV) centers in diamond. The transformer employs four optical fibers to realize power delivery and signal transmission between the high-voltage and low-voltage sides, completely eliminating metallic electrical connections. The system achieves a magnetic sensitivity of 4.05 nT/Hz 1/2 , with highly linear current response ( R 2 = 0.998) and a measurement accuracy better than 1%. This all-fiber architecture satisfies the dual constraints of high-voltage insulation and low power consumption while preserving the metrological precision of quantum sensing, providing a viable pathway toward non-invasive precision current monitoring in next-generation smart substations.
Quantum sensors encompass a diverse class of devices that exploit quantum coherence to detect weak or nanoscale signals. As their behavior is tied to physical constants, quantum sensors can achieve accuracy, repeatability, and precision approaching fundamental limits [1, 2]. As a result, these sensors have shown utility in a wide range of applications in both science and engineering leading to innovations. Among many solid-state spin systems, nitrogen-vacancy (NV) centers in diamonds have attracted considerable attention as a leading platform in many fields of quantum technologies, from quantum sensing to information processing and communication applications. They have superior physical properties, and their quantum coherence is preserved even at room temperature. The energy levels of NV centers are sensitive to magnetic fields, electric fields, strain, and temperature, and the spatial resolution is scalable from nanometers to millimeters. Therefore, diamond quantum sensors are distinctive sensors with multimodality and span scalable application fields. To realize an ideal quantum sensor for applications, the technical challenges in the sensor materials and the quantum control techniques, such as coherent microwave spin manipulation, effective optical spin-state initialization, and readout, have been developed. This chapter briefly explains the sensing principle using NV centers and then introduces sensor systems for biomedical applications, and monitoring of batteries for electric vehicles and internal power devices.
Diamond nitrogen-vacancy (NV) centers are widely studied for quantum sensing in multiple physical fields due to their long coherence time and room-temperature optical readout. However, accurately decoupling and extracting signals for individual fields from fluorescence remains a major challenge. In this work, by establishing the spatial configuration between the four axes of the NV center and the directions of the externally applied electric and magnetic fields, the resonance frequency shifts of two pairs in the ODMR spectrum are exclusively induced by the electric field, whereas those of the other two pairs are exclusively induced by the magnetic field. Consequently, effective decoupling and readout of the electric field signal are realized. The experiments measure electric fields from 0 to 20 kV/cm in the diamond sample, revealing a linear relationship between the resonance frequency shift and the applied electric field, with coefficients 0.1713MHz/(kV/cm) and 0.1660MHz/(kV/cm) matching the NV center’s linear Stark effect, laying the foundation for subsequent research on electric field measurement.
Nitrogen-vacancy (NV) centres in diamond are promising quantum systems for sensing applications due to their quantum coherence, optical addressability, and robust performance even at room temperature [1], [2]. These properties allow for the precise measurement of environmental parameters, such as magnetic fields [2], electric fields, strain, and temperature [1]–[4]. This work focuses on a portable multisensing platform based on NV centres, examining its performance across a temperature range of -20°C to 120°C [2]. Understanding the temperature dependence of the spectral features of NV centres is crucial not only to assess its capabilities for multisensing, but also for optimising the device for diverse operating conditions and for ensuring the precision and reliability of quantum measurements [3]. While many studies focus on low temperatures or individual NV centres, this work focuses on an ensemble of NV centres at relatively high temperatures, which is more suitable for portable sensors [1], [5]. This work is novel as it provides a comprehensive study of a portable NV -based multisensor's performance at relatively high temperatures, crucial for real-world applications [1].
Nitrogen Vacancy (NV) centers are point defects in diamond that allow magnetic field sensing based on Optically Detected Magnetic Resonance (ODMR). They are processed in ultrapure single-domain CVD grown diamond crystals and can be operated at room temperature. This results in solid-state sensors with a wide variety of applications. Ensemble of NV centers can be used to perform wide-field magnetic imaging with sensitivity in the nT range. Single NV centers can also be processed, which allows sensing at the atomic scale. This possibility, combined with its unique coherence properties, make NV center an ideal candidate for quantum sensing.