Investigating the atomic structures and electronic properties of WS2thin films with sulfur vacancies via a neural network potential-aided first-principles study

Autor: Otsuka, Ryuji, Shimizu, Koji, Wakabayashi, Hitoshi, Watanabe, Satoshi
Zdroj: Applied Physics Express (APEX); November 2024, Vol. 17 Issue: 11 p115501-115501, 1p
Abstrakt: Transition metal dichalcogenides are promising materials for high-performance electronics, whereas the impact of defects on their electronic properties remains elusive. Here, we employ neural network potentials (NNPs) constructed from density functional theory (DFT) data to investigate defect-laden WS2thin films. Molecular dynamics simulations reveal that at low defect concentrations (S/W ratio of 1.9), single sulfur vacancies are predominant. Conversely, at high defect concentrations (S/W ratio of 1.7), complex defects with short lifetimes appear. Additionally, DFT results indicate that the band gap persists at S/W = 1.9 but disappears at 1.7, aligning with observed device degradation at high defect concentrations.
Databáze: Supplemental Index