Single qubit in solid-state materials recently emerges as a versatile platform for quantum information. Among them, the nitrogen vacancy (NV) centre in diamond has become a powerful tool in quantum sensing for detecting various physics parameters, including electric and magnetic fields, temperature, force, strain, with ultimate precision and resolutions. It has been widely used in different conditions, from samples in ambient to samples in ultra-high pressure and low temperature. It can detect quantum phase transitions as well as neuron activities. Here we give a general review on both the physics of the sensing mechanism and protocols and applications.
Single qubit in solid-state materials recently emerges as a versatile platform for quantum information. Among them, the nitrogen vacancy (NV) centre in diamond has become a powerful tool in quantum sensing for detecting various physics parameters, including electric and magnetic fields, temperature, force, strain, with ultimate precision and resolutions. It has been widely used in different conditions, from samples in ambient to samples in ultra-high pressure and low temperature. It can detect quantum phase transitions as well as neuron activities. Here we give a general review on both the physics of the sensing mechanism and protocols and applications.
Abstract The detection of single quantum systems can reveal information that would be averaged out in traditional techniques based on ensemble measurements. The nitrogen-vacancy (NV) centers in diamond have shown brilliant prospects of performance as quantum bits and atomic sensors under ambient conditions, such as ultra-long coherence time, high fidelity control and readout of the spin state. In particular, the sensitivity of the NV center spin levels to external environmental changes makes it a versatile detector capable of measuring various physical quantities, such as temperature, strain, electric fields and magnetic fields. In this paper, we review recent progress in NV-based quantum metrology, and speculate on its future.
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.
Extreme conditions, such as ultra-low temperatures, high pressures, and strong magnetic fields, are critical to producing and studying exotic states of matter. To measure physical properties under extreme conditions, the advanced sensing schemes are required. As a promising quantum sensor, the diamond nitrogen-vacancy (NV) center can detect magnetic field, electronic field, pressure, and temperature with high sensitivity. Considering its nanoscale spatial resolution and ultra-wide working range, the diamond quantum sensing can play an important role in frontier studies involving extreme conditions. This paper reviews the spin and optical properties of diamond NV center under extreme conditions, including low temperature, high temperature, zero field, strong magnetic fields, and high pressures. The opportunities and challenges of diamond quantum sensing under extreme conditions are discussed. The basic knowledge of spin-based quantum sensing and its applications under extreme conditions are also covered.
Quantum sensing is a quantum technology for ultrasensitive detection, which is particularly useful for sensing weak signals at the nanoscale. Nitrogen vacancy centers in diamond, thanks to their superb quantum coherence under ambient conditions and the stability of the material in extreme and complicated environments, have been demonstrated as promising quantum probes in multi-parameter sensing. Their spin properties make them particularly sensitive to magnetic fields, but they are insensitive to temperature, electric field, pressure, etc., and even immune to some bio-parameters (e.g., pH and glucose concentration). Recently, hybrid quantum sensing has emerged as a promising avenue for further enhancing the capabilities of diamond sensors. Different techniques can potentially improve the sensitivity, range of detectable parameters, and sensing frequencies of diamond sensors. This review provides an overview of hybrid quantum sensing using diamond. We first give a brief introduction to quantum sensing using diamond, and then review various hybrid sensing schemes that have been developed to enhance the sensing capabilities of diamond sensors. Finally, the potential applications and challenges associated with hybrid quantum sensing in diamond are discussed.
Pressure has been established as a powerful way of tuning material properties and studying various exotic quantum phases. Nonetheless, measurements under pressure are no trivial matter. To ensure a stable pressure environment, several experimental restrictions must be imposed including the limited size of a sample chamber. These have created difficulties in assembling high-pressure devices and conducting measurements. Hence, novel sensing methods that are robust and compatible with high-pressure devices under pressure are highly in demand. In this review, we discuss the nitrogen-vacancy (NV) center in diamond as a versatile quantum sensor under pressure. The excellent sensitivity and superior resolution of the NV center enable exciting developments in recent years. The NV center has great potential in sensing under pressure, especially beneficial to magnetic-related measurements.