Due to the limitation of standard quantum limit (SQL), traditional laser interferometry based micro angle attitude measurement technology cannot further improve its measurement accuracy. Applying quantum weak value measurement technology to micro angle measurement will greatly improve its measurement accuracy. This article introduces the basic principle of quantum weak value measurement, and introduces the research progress in micro bit angle/displacement measurement using quantum weak value measurement technology in recent years. The future application trend of quantum weak measurement technology in micro angle is analyzed and prospected.
Due to the limitation of standard quantum limit (SQL), traditional laser interferometry based micro angle attitude measurement technology cannot further improve its measurement accuracy. Applying quantum weak value measurement technology to micro angle measurement will greatly improve its measurement accuracy. This article introduces the basic principle of quantum weak value measurement, and introduces the research progress in micro bit angle/displacement measurement using quantum weak value measurement technology in recent years. The future application trend of quantum weak measurement technology in micro angle is analyzed and prospected.
Abstract With the rapid development of micro‐nano fabrication technology, micro‐optical gyroscope technology has shown tremendous potential in integration, miniaturization, and sensitivity. The micro‐optical gyroscope is closely related to the performance of the gyroscopic system, which is realized by the light‐matter interaction and resonance enhancement. Currently, the detection range of micro‐optical gyroscopes extends from millimeter‐scale physical mechanical motion to molecular vibrations at the nanometer scale; however, their precision is challenging to surpass the standard quantum limit. The primary research objective of quantum precision measurement is to utilize quantum resources to conduct quantum‐enhanced measurements on physical system quantities, thereby surpassing the quantum limit and improving parameter measurement accuracy. In recent years, due to the rapid development in the field of quantum precision measurement, quantum gyroscope has made great progress in practical and engineering. In the future, by replacing traditional accelerometers and gyroscopes, it may be possible to develop highly integrated, low‐power, and low‐drift quantum inertial navigation systems. Based on the information disclosed by journals, conferences, and related research institutions, this paper briefly outlines the development status, basic principles, and corresponding challenges of the micro‐optical gyroscope. Additionally, this paper introduces the current theoretical and experimental progress of quantum‐enhanced gyroscopes.
Quantum precision measurement is based on the basic principle of quantum mechanics by using the interaction between light, atoms and magnetism to measure physical quantities, also known as precision measurements based on microscopic particle systems and their quantum states. As an important means of quantum precision measurement, interferometer precision measurement technology has great application value in quantum communication. The linear interferometer measures the magnitude of the physical quantity by using the phase change obtained from the measurements, but measurement accuracy is limited and unable to meet the requirements of today's scientific problems for the precision measurement of some physical quantities. On this basis, nonlinear interferometer is able to take advantage of the quantum entangled state, that is, using the two light fields of quantum correlation characteristics to realize quantum enhanced precision measurement, thus greatly improving the measurement sensitivity, Therefore, the scope of application is wider, but the preparation of quantum entangled states has many limitations in practical manipulation. With the maturity of experimental conditions and technology, how to use both of these interferometers to further improve the measurement accuracy of the phase signal so as to break the limitation to shot noise, breaking the standard quantum limit and even approaching to the Heisenberg limit has become a frontier research topic . In this paper, we introduce several methods to improve the accuracy of parameter evaluation in the measurement process by using linear (including an atomic/photon interferometer) and nonlinear interferometer to call quantum resources at different stages. High-precision measurement can be achieved by inputting non-classical states into the interferometer, such as compressed state, bi-fock state, and NOON state. And we also introduce the weak measurement developed for the direct observation of quantum states and its application to non-Hermitian systems, and the multiparameter measurement proposed to eliminate the accuracy balance between parameters. Compared with the first two measurement methods, weak measurement method is based on the weak value amplification principle of an indirect measurement. Measurements are performed virtually without perturbing the quantum system, which does not lead the wave function to collapse, the weak value of the real and virtual part have different physical significance, The combination of weak measurement theory and non-Hermitian system also further improves the measurement sensitivity. Multi-parameter measurement uses quantum entanglement, quantum control and other quantum resources to make the measurement progress reach the Heisenberg limit, which is the current research hotspot in the field of precision measurement. Furthermore, we present a conjecture whether there will be multi-atomic mixing measurements based on atomic spin effects or ultra-high sensitivity measurement instruments with precision of fT or even aT by using other particles detection. Finally, several measurement methods are analyzed and compared with each other, and the development prospect of quantum precision measurement is forecasted.
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 ability to manipulate light has allowed scientists to verify fundamental theories of physics and to develop a new generation of technologies that use photons as a primary resource. Recent developments in quantum measurement theory have offered new alternatives to approach some of the most remarkable problems in quantum physics. Consequently, the principles of quantum mechanics have been exploited in the development of quantum technologies such as optical metrology, quantum communication, and quantum information. In recent years, weak measurements and two of its most remarkable variants: weak value amplification and direct measurement, have been developed and are considered important resources for quantum applications. In this paper, we discuss weak measurements and some significant applications of weak values. We elaborate on how distinct forms of weak values are used to observe and amplify small effects or to directly measure the quantum wave function of photons, a crucial task for schemes for quantum communication and quantum information. We also review some of the most recent methods for weak value amplification and direct measurement that our group has developed.
Quantum metrology technology is an advanced measurement method, which can achieve the accuracy that classical metrology is difficult to measure, and supplement the accuracy and stability defects caused by the standard quantum limit. In addition, reproducing quantum effects and quantum phenomena into units of metrology, which is obviously superior to the traditional measurement technology in terms of measurement accuracy, sensitivity and stability that could realize the quantum value transfer and traceability activities. With the development of laser cooling and trapping atom technology, the pressure measurement range of cold atom quantum-based vacuum metrology(CAVM) may reach 10-4~10-10 Pa or even lower . Benefiting from the loss rate of cold atoms in CAVM is only controlled by the collision cross section between cold atoms and gases, CAVM has the potential to develop into a emerging generation of vacuum metrology technology27. In this paper, the basic concept, structure and working principle of magneto-optical traps(MOT) for laser cooling atoms and trapping atoms are briefly described; Then, the basic principle of the CAVM is introduced. Furthermore, through collecting and sorting out a large number of literature about this technology, the advantages and key technologies of this technique in recent years are comprehensively analyzed and summarized; Finally, the developing trend of the CAVM is prospected.
With the progress of laser cooling and other atom optics technologies, the cold atom interferometry gyroscope based on cold atom wave is developing rapidly, and it promises to be a novel gyroscope technology in inertial navigation areas. The research status of cold atom interferometry gyroscope and the principle of atom interferometry are introduced, and a comparative analysis of the characteristics among the three distinct types of cold atom interferometry gyroscopes in Stanford University, Observatoire de Paris and Hanover University is carried out. The improving schemes and developing prospects of cold atom interferometry gyroscope are discussed by focusing on its current limitations, aiming at its wider application in inertial navigation fields.