First-principles studies of light-matter interactions in two-dimensional structures

I will beging with an introduction of light-matter interactions and excited states, such as quasiparticles and excitons, and how to calculate them by first-principles many-body perturbation theory. Then I will focus on simulations of light-matter interactions of emerging two-dimensional (2D) anisotropic black phosphorus and magnetic materials. By calculating electron-electron and electron-hole interactions, we can predict and explain important measurements. Finally, I will go beyond linear light-matter interactions and propose enhanced charge and spin photocurrents in layered magnetic axion insulators and non-centrosymmetric semiconductors, giving hope to realizing light-driven pure spin current.