Ultrafast Optical Spectroscopy on Materials with Strong Spin-Orbit Coupling
Jingbo Qi (齐静波)
University of Electronic Science and Technology of China (电子科技大学)
Abstract: Ultrafast optical spectroscopy has been widely used to explore and control the dynamical properties of various materials. Many related findings have great potential in applications such as ultrafast opto-electronics, coherent light sources, logic or memory devices etc.. Here, we show several experimental investigations on materials with strong spin-orbit coupling using this technique. Specifically: (1) We demonstrate that transient optical reflectivity or transmissivity measurements at fundamental frequency can reveal and manipulate the carrier and spin dynamics in the topological materials; (2) In the nonlinear optics regime, we show that giant second harmonic generation and broadband terahertz emission can emerge in the topological semimetals and heterostructures with heavy metal.
Jingbo Qi, professor in the School of Electronic Science and Engineering at University of Electronic Science and Technology of China. He got his Ph.D. from Vanderbilt University (USA). Before moving back to China, he was a postdoctoral associate in the National High Magnetic Field Laboratory and Los Alamos National Laboratory, respectively. His main research interest focuses on using the ultrafast optical spectroscopy and terahertz spectroscopy to study the dynamical properties in various material systems. In recent years, he has made great progresses in searching the novel terahertz radiation mechanisms, ultrafast coherent control of the spin-related properties in topological materials, and revealing the hidden collective properties in strongly correlated materials. The related works are published in scientific journals such as Phys. Rev. Lett., Nat. Commun. and so on.