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arXiv · 2107.13096

Trapping Interlayer Excitons in van der Waals Heterostructures by Potential Arrays

Darien J. Morrow·Xuedan Ma
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Abstract

Transition metal dichalcogenide heterostructures can host interlayer excitons (IXs), which consist of electrons and holes spatially separated in different layers. IXs possess permanent dipoles and have proven to offer a wealth of novel physics. We develop a discrete, random-walk model which includes annihilation and repulsion interactions among IXs. Using this model, we simulate the trapping of IXs in traps of different depths, densities, and shapes. Our results show that dipole-dipole interactions play an important role in regulating IX trapping. The effects of dipole interactions can be mitigated with small, deep traps which are realizable with atomic defects and moire potentials.

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BibTeXRIS

Darien J. Morrow, Xuedan Ma. 2021-07-27. Trapping Interlayer Excitons in van der Waals Heterostructures by Potential Arrays. https://doi.org/10.1103/physrevb.104.195302

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