- Open Access
Real-time exciton dynamics in two-dimensional materials under ultrashort laser pulses
Phys. Rev. B 114, 045127 – Published 27 July, 2026
DOI: https://doi.org/10.1103/ppgw-myxb
Abstract
The optical response of two-dimensional materials is often significantly impacted by excitonic effects due to the reduced screening of attractive Coulomb interactions in low-dimensional systems. Accurate modeling of exciton formation and real-time dynamics is essential to understanding their ultrafast optical properties. In this study, we theoretically investigate the exciton dynamics in a two-dimensional hexagonal boron nitride (h-BN) and a germanium sulfide (GeS) monolayers exposed to an ultrashort laser pulse. We analyze the system's response to the external field in one- and two-photon excitation regimes. For our calculations, we combine a state-of-the-art ab initio approach to study exciton dynamics with a highly precise numerical scheme. We incorporate electron-hole interactions through a nonlocal self-energy operator derived from the many-body perturbation theory (MBPT) within the time-dependent adiabatic approximation. We implement this approach using the full-electron method in the all-electron exciting package. Our results elucidate the role of many-body effects in shaping ultrafast excitonic processes in two-dimensional materials, contributing to the fundamental understanding necessary for optoelectronic and photonic applications.
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