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arXiv · 1804.04599

Single-layer $1T'$-MoS$_2$ under electron irradiation from $ab$ $initio$ molecular dynamics

Michele Pizzochero·Oleg V. Yazyev
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Abstract

Irradiation with high-energy particles has recently emerged as an effective tool for tailoring the properties of two-dimensional transition metal dichalcogenides. In order to carry out an atomically-precise manipulation of the lattice, a detailed understanding of the beam-induced events occurring at the atomic scale is necessary. Here, we investigate the response of $1T'$-MoS$_2$ to the electron irradiation by $ab$ $initio$ molecular dynamics means. Our simulations suggest that an electron beam with energy smaller than 75 keV does not result in any knock-on damage. The displacement threshold energies are different for the two nonequivalent sulfur atoms in $1T'$-MoS$_2$ and strongly depend on whether the top or bottom chalcogen layer is considered. As a result, a careful tuning of the beam energy can promote the formation of ordered defects in the sample. We further discuss the effect of the electron irradiation in the neighborhood of a defective site, the mobility of the sulfur vacancies created and their tendency to aggregate. Overall, our work provides useful guidelines for the imaging and the defect engineering of $1T'$-MoS$_2$ using electron microscopy.

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Michele Pizzochero, Oleg V. Yazyev. 2018-04-12. Single-layer $1T'$-MoS$_2$ under electron irradiation from $ab$ $initio$ molecular dynamics. https://doi.org/10.1088/2053-1583%2Faab279

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