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arXiv · 2209.14420

Charge quenching at defect states in transition metal dichalcogenide-graphene van der Waals heterobilayers

Daniel Hernangómez-Pérez·Andrea Donarini·Sivan Refaely-Abramson
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Abstract

We study the dynamical properties of point-like defects, represented by monoatomic chalcogen vacancies, in WS$_2$-graphene and MoS$_2$-graphene heterobilayers. Employing a multidisciplinary approach based on the combination of ab initio, model Hamiltonian and density matrix techniques, we propose a minimal interacting model that allows for the calculation of electronic transition times associated to population and depopulation of the vacancy by an additional electron. We obtain the "coarse-grained" semiclassical dynamics by means of a master equation approach and discuss the potential role of virtual charge fluctuations in the internal dynamics of impurity quasi-degenerate states. The interplay between the symmetry of the lattice and the spin degree of freedom through the spin-orbit interaction and its impact on charge quenching is studied in detail.

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Daniel Hernangómez-Pérez, Andrea Donarini, Sivan Refaely-Abramson. 2022-09-28. Charge quenching at defect states in transition metal dichalcogenide-graphene van der Waals heterobilayers. https://doi.org/10.1103/physrevb.107.075419

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