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arXiv · 2606.22014

Stacking-Directed Polarization and Excitonic Engineering in MoS$_2$/MoSe$_2$ van der Waals Heterostructures

Mohammed El Amine Miloudi·Oliver Kühn
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Abstract

The stacking-dependent polarization and excitonic response of MoS$_2$/MoSe$_2$ heterostructures were investigated using GW+BSE many-body perturbation theory. While homobilayer MoS$_2$ exhibited a switchable interlayer dipole driven by registry-induced symmetry breaking, the MoS$_2$/MoSe$_2$ hetero-interface remained pinned by the intrinsic chemical potential mismatch between sulfur and selenium. In 2L-MoS$_2$/MoSe$_2$ trilayers, the stacking sequence enabled a deterministic control of photogenerated electrons between the central and bottom MoS$_2$ layers, governed by internal electric fields and quasiparticle band-edge shifts of 60--70~meV. Our calculations predicted a 36~meV interlayer excitonic shift, in remarkable agreement with recent experiments. These results elucidate the microscopic link between atomic registry and many-body interactions, establishing transition metal dichalcogenide trilayers as a potential platform for sliding ferroelectricity and programmable optoelectronic functionalities.

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Mohammed El Amine Miloudi, Oliver Kühn. 2026-06-20. Stacking-Directed Polarization and Excitonic Engineering in MoS$_2$/MoSe$_2$ van der Waals Heterostructures. https://arxiv.org/abs/2606.22014

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