Transition metal dichalcogenide (TMD) materials have attracted substantial interest due to their remarkable excitonic, optical, electrical, and mechanical properties, which are highly dependent on their crystal structure. Controlling the crystal structure of these materials is essential for fine-tuning their performance, e.g., linear and nonlinear optical, as well as charge transport properties. While various phase-switching TMD materials, like molybdenum telluride (MoTe2), are available, their transitions are often irreversible. Here, we investigate the mechanism of a light-induced reversible phase transition in mono- and bilayer flakes of rhenium disulfide (ReS2). Our observations, based on scanning transmission electron microscopy, nonlinear spectroscopy, and density functional theory calculations, reveal a transition from the ground T′′ (double distorted T) to the metastable H′ (distorted H) phase under femtosecond laser irradiation or influence of highly-energetic electrons. We show that the formation of sulfur vacancies facilitates this phenomenon. Our findings pave the way towards actively manipulating the crystal structure of ReS2 and possibly its heterostructures.
@article{arxiv.2405.12859,
title = {Defect-assisted reversible phase transition in mono- and few-layer ReS$_2$},
author = {George Zograf and Andrew B. Yankovich and Betül Küçüköz and Abhay V. Agrawal and Alexander Yu. Polyakov and Joachim Ciers and Fredrik Eriksson and Åsa Haglund and Paul Erhart and Tomasz J. Antosiewicz and Eva Olsson and Timur O. Shegai},
journal= {arXiv preprint arXiv:2405.12859},
year = {2024}
}