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arXiv · 2103.13386

Role of defects in ultrafast charge recombination in monolayer MoS$_2$

Raquel Esteban-Puyuelo·Biplab Sanyal
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Abstract

In this work, we have systematically studied the role of point defects in the recombination time of monolayer MoS$_2$ using time-dependent ab initio non-adiabatic molecular dynamics simulations. Various types of point defects, such as S vacancy, S interstitial, Mo vacancy and Mo interstitial have been considered. We show that defects strongly accelerate the electron-hole recombination, especially interstitial S atoms do that by 3 orders of magnitude higher compared to pristine MoS$_2$. Mo defects (both vacancy and interstitial) introduce a multitude of de-excitation pathways via various defect levels in the energy gap. The results of this study provide some fundamental understanding of photoinduced de-excitation dynamics in presence of defects in highly technologically relevant 2D MoS$_2$.

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Raquel Esteban-Puyuelo, Biplab Sanyal. 2021-03-24. Role of defects in ultrafast charge recombination in monolayer MoS$_2$. https://doi.org/10.1103/physrevb.103.235433

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