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arXiv · 2109.15209

Real-time GW: Toward an ab initio description of the ultrafast carrier and exciton dynamics in two-dimensional materials

E. Perfetto·Y. Pavlyukh·G. Stefanucci
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Abstract

We demonstrate the feasibility of the time-linear scaling formulation of the $GW$ method [Phys. Rev. Lett. {\bf 124}, 076601 (2020)] for {\it ab initio} simulations of optically driven two-dimensional materials. The time-dependent $GW$ equations are derived and solved numerically in the basis of Bloch states. We address carrier multiplication and relaxation in photo-excited graphene and find deviations from the typical exponential behavior predicted by the Markovian Boltzmann approach. For resonantly pumped semiconductor we discover a self-sustained screening cascade leading to the Mott transition of coherent excitons. Our results draw attention to the importance of non-Markovian and dynamical screening effects in out-of-equilibrium phenomena.

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E. Perfetto, Y. Pavlyukh, G. Stefanucci. 2021-09-30. Real-time GW: Toward an ab initio description of the ultrafast carrier and exciton dynamics in two-dimensional materials. https://doi.org/10.1103/physrevlett.128.016801

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