Abstract: In recent years, with the rapid development of the ultrafast field, terahertz radiation has shown increasingly innovative applications in scientific research, such as biomedicine, materials science, communication technology, imaging field and so on. However, the physical mechanism of strongfield terahertz radiation based on tilted wavefront phasematching optical rectification has a long history, known as Cherenkov effect, which was discovered over a century ago. Undergraduate students majoring in physics learn Cherenkov effect at first time as an optional topic in the “Doppler Effect” section of chapter “Wave” in mechanics. For a long time, the Cherenkov effect has not drawn sufficient attention. As a physical concept, Cherenkov effect involves multiple courses, starting from the Mach cone in mechanics and connecting to Cherenkov radiation in electrodynamics. As for the application level, Cherenkov effect plays a very important role in modern world, both technological and scientific fields. By comparing and analyzing the Cherenkov effect with the physical mechanism of terahertz radiation based on wavefronttilted phasematching optical rectification, we will not only deepen students' understanding of basic physical concepts but also guides them to explore the frontiers of science and technology, truly practicing the educational philosophy of “leading science and technology coming from the theory and merging into the theory”.

Key words: fluctuation, Doppler effect, Cherenkov effect, terahertz radiation, innovative teaching method