Quantum materials simulations: Excited-state dynamics and quantum transport

Excited-state dynamics simulation enables us to explore a wide variety of nonequilibrium phenomena remaining uncharted in the field of physics, (bio)chemistry, and materials science. To elucidate electron-enhanced atomic-layer deposition, we simulate inelastic electron scattering followed by nonadiabatic molecular dynamics using time-dependent density functional theory (TDDFT) along with Ehrenfest dynamics. Also, photodegradation of hybrid perovskite solar cells is studied in terms of quantum chaos of the molecular cation using TDDFT. Quantum transport emerges when the wave nature of matter plays a role. We utilize the nonequilibrium Green’s function formalism (NEGF) formalism to study coherent/incoherent quantum transport and localization in disordered systems, e.g., amorphous semiconductors and amorphous/crystalline hetero-phase materials. Quantum information science has the potential for solving problems that no one can ever solve in classical technology. We are devoted to understanding and predicting materials properties relevant to the performance of solid-state qubits. From this perspective, we study edge-contact effects on the transparency of graphene Josephson junctions for topological superconductivity. The dissertation demonstrates a wide range of applications, where excited-state dynamics and quantum transport emerge, and exhibits the potential of the rather unconventional but advanced computational approaches in the field of materials research.