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arXiv · 2112.08054

Hybrid excitations at the interface between a MoS$_2$ monolayer and organic molecules: a first-principles study

Ignacio Gonzalez Oliva·Fabio Caruso·Pasquale Pavone·Claudia Draxl
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Abstract

We present a first-principles investigation of the electronic and optical properties of hybrid organic-inorganic interfaces consisting of MoS$_2$ monolayer and the $\pi$-conjugate molecules pyrene and pyridine. For both hybrid systems, the quasi-particle band structure obtained from the $G_0W_0$ approximation shows -- in contrast to density-functional theory -- level alignment of type II, owing to the mutual dynamical screening of the interface constituents. $\textit{Ab initio}$ calculations of the absorption spectrum based on the Bethe-Salpeter equation reveal besides intra-layer excitons on the MoS$_2$ side, hybrid as well as charge-transfer excitons at the interface. These findings indicate that hybrid systems consisting of semiconducting transition-metal dichalcogenides and organic $\pi$-conjugate molecules can host a rich variety of optical excitations and thus provide a promising venue to explore many-body interactions and exciton physics in low dimensionality.

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Ignacio Gonzalez Oliva, Fabio Caruso, Pasquale Pavone, Claudia Draxl. 2021-12-15. Hybrid excitations at the interface between a MoS$_2$ monolayer and organic molecules: a first-principles study. https://arxiv.org/abs/2112.08054

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