（1.School of Integrated Circuit Science and Engineering, Beihang University, Beijing 100191, China) （2.Shenzhen Institute for Quantum Science and Engineering, Southern University of Science and Technology, Shenzhen 518055, China)
In recent years, the traditional semiconductor technology has encountered bottlenecks, and the rate of Moore’s Law has slowed down. It is urgent for people to find the next generation of new electronic components. With the vigorous development of spintronics, electron spin has attracted extensive attention as a medium for information transmission. In the field of spintronics, spin waves, as collective precessions of electron spins, show many advantages beyond electronic devices. Magnonics aims to use the characteristics of spin waves to realize the fabrication of low-power computing devices, providing a reliable theoretical basis and technical route for the development and application of next-generation electronic components. The physics of spin waves is very rich, for example, spin waves can be confined and guided, and they can also be amplified. Spin waves may be generated with variable degrees of coherency, depending on the excitation methods. This article mainly focuses on coherent spin waves, and we review the recent research progress of spin waves, including magnonic crystals, the conversion of spin waves and currents, the excitation and detection of the exchange spin waves, the coupled systems based on the spin waves, spin-wave logic devices. And the development direction of spin wave electronics is also prospected.