Title: Light-induced Band Engineering in 2D Materials and Topological Materials

Speaker: Prof. Tang Peizhe, Beihang University

Abstract: Interactions between light and matter allow the realization of out-of-equilibrium states in quantum solids and lead to the emergence of new correlated states. We report the observation of the Floquet engineering and the light-induced band renormalization in black phosphorus. Utilizing time-dependent density functional theory (TDDFT), we study the dynamical evolution of the Floquet states in the photoemission spectra of monolayer black phosphorus. By applying group theory, we incorporate the pseudospin degree of freedom to indicate the selection rules for these light-induced sidebands, which are governed by the symmetries of both the material and the lasers and determine the distribution of spectral weights. Furthermore, we will introduce our recent progresses on excitonic effect in moiré systems and light induced magnetism.