Using quantum weak measurement technology, the very weak interaction can cause significant observation effects. It plays important roles in observing the extreme weak physical effect, quantum parameter estimation, quantum state tomography and so on. It has become a research hotspot in the field of quantum measurement. Based on the Stern-Gerlach experiment as the starting point, this paper explains the physical image of quantum weak measurement by using the knowledge of elementary quantum mechanics, and further introduces the frontier development of related fields. This paper can deepen physics teachers' understanding of quantum weak measurement, which is a frontier physical problem, and also help students to establish a clear physical image. The introduction of cutting-edge technology in the teaching process also helps to stimulate students' interest and enthusiasm for active exploration and further research. This paper aims to build a bridge between basic physics principles and high-tech, which is beneficial for college physics teachers to broaden scientific thoughts and enhance academic taste.
Using quantum weak measurement technology, the very weak interaction can cause significant observation effects. It plays important roles in observing the extreme weak physical effect, quantum parameter estimation, quantum state tomography and so on. It has become a research hotspot in the field of quantum measurement. Based on the Stern-Gerlach experiment as the starting point, this paper explains the physical image of quantum weak measurement by using the knowledge of elementary quantum mechanics, and further introduces the frontier development of related fields. This paper can deepen physics teachers' understanding of quantum weak measurement, which is a frontier physical problem, and also help students to establish a clear physical image. The introduction of cutting-edge technology in the teaching process also helps to stimulate students' interest and enthusiasm for active exploration and further research. This paper aims to build a bridge between basic physics principles and high-tech, which is beneficial for college physics teachers to broaden scientific thoughts and enhance academic taste.
The Stern–Gerlach experiment can play an important role in teaching the formalism of quantum mechanics. In the context of a finite-dimensional Hilbert space students can learn how to prepare a specific quantum state starting from an arbitrary state, issues related to the time evolution of the wave function and quantum measurement. The Stern–Gerlach experiment can also be used to teach the distinction between the physical space where the experiment is performed and the Hilbert space where the state of the system lies, and how information about the state of the system in the Hilbert space can be exploited to interpret the possible outcomes of the experiment in physical space. Students can learn the advantages of choosing an appropriate basis to make predictions about the outcomes of experiments with different arrangements of Stern–Gerlach devices. The latter can also help students understand that an ensemble of identically prepared systems is not the same as a mixture. We discuss student difficulties with the Stern–Gerlach experiment based on written tests and interviews with advanced undergraduate and graduate students in quantum mechanics courses. We also discuss preliminary data which suggest that the Quantum Interactive Learning Tutorial on the Stern–Gerlach experiment is helpful in improving student understanding of these concepts.
During the teaching process, if the teacher could take the frontier application of science and technology as the traction, explain the principles of cutting-edge scientific and technological progress in the language of college physics, and shorten the distance between basic courses and cutting-edge applications, the students' interest in learning physics will be promoted and their understanding of basic physics principles will be deepen. Taking quantum key distribution as an example, this paper explains the basic principle of the classical BB84 scheme with the polarization content in college physics, and expounds the actual implementation of this scheme, aiming to show that there is a considerable distance between the theoretical scheme and the actual implementation. In order to stimulate students' interest and enthusiasm for active exploration, the latest research progress and current main research directions in the field of quantum communication are also introduced. This is a pioneering attempt to bridge the fundamental physics theory and frontier technolies, which is worth promoting in college physics teaching in the context of emerging engineering education.
This popular undergraduate quantum mechanics textbook is now available in a more affordable printing from Cambridge University Press. Unlike many other books on quantum mechanics, this text begins by examining experimental quantum phenomena such as the Stern-Gerlach experiment and spin measurements, using them as the basis for developing the theoretical principles of quantum mechanics. Dirac notation is developed from the outset, offering an intuitive and powerful mathematical toolset for calculation, and familiarizing students with this important notational system. This non-traditional approach is designed to deepen students' conceptual understanding of the subject, and has been extensively class tested. Suitable for undergraduate physics students, worked examples are included throughout and end of chapter problems act to reinforce and extend important concepts. Additional activities for students are provided online, including interactive simulations of Stern-Gerlach experiments, and a fully worked solutions manual is available for instructors.
This popular undergraduate quantum mechanics textbook is now available in a more affordable printing from Cambridge University Press. Unlike many other books on quantum mechanics, this text begins by examining experimental quantum phenomena such as the Stern-Gerlach experiment and spin measurements, using them as the basis for developing the theoretical principles of quantum mechanics. Dirac notation is developed from the outset, offering an intuitive and powerful mathematical toolset for calculation, and familiarizing students with this important notational system. This non-traditional approach is designed to deepen students' conceptual understanding of the subject, and has been extensively class tested. Suitable for undergraduate physics students, worked examples are included throughout and end of chapter problems act to reinforce and extend important concepts. Additional activities for students are provided online, including interactive simulations of Stern-Gerlach experiments, and a fully worked solutions manual is available for instructors.
The Stern-Gerlach experiment holds key role for students, particularly those studying quantum mechanics, modern physics, atomic physics, and physics education.It is one of the simplest experiments that demonstrates that the microscopic world does not behave accordingly withdynamics of classical physics, thusthe Stern-Gerlach experiment allows students to follow a logical progression: Classical expectation → Experimental observation → Failure of classical explanation → Quantum hypothesis → Spin states → Mathematical formulation → Quantum measurement.
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.