We are interested in investigating and predicting physical properties of condensed matter using computers based on quantum mechanics. We are also interested in developing new theoretical and computational methods for better understanding the nature of condensed matter and quantum materials. Currently, the main approaches adopted for our research are based on the first-principles calculations within density functional theory and tight-binding models. Density functional theory (DFT) and the extended time-dependent density functional theory (TDDFT) provide a shortcut to access the many-body properties of a system and are widely used in the electronic-structure calculations.