First-Principles Investigations of Quantum Defects in Two-Dimensional Transition Metal Dichalcogenides

Quantum defects, considerred as artificial atoms embedded within host materials, are key components in realizing applications in quantum information science. Low-dimensional materials, such as transition metal dichalcogenides (TMDs), are particularly promising hosts due to their inherent quantum confinement nature, long projected spin coherence time, and strong spin-orbit coupling (SOC). In this study, we focus on two common point defects in monolayer tungsten disulfide (WS₂): vacancies and carbon substitutions. We used computational modeling techniques along with hybrid functionals and SOC, factoring in the nonunique exact exchange fraction characteristic [1] of low-dimensional materials, to analyze the thermodynamic stability and electronic structures of these defects. Our results, combined with experimental characterizations, provide new insights into the properties of these defects, encouraging further research into the understanding and design of quantum defects in TMDs.<br/><br/>[1]. Chen, Wei, et al. "Nonunique fraction of Fock exchange for defects in two-dimensional materials." Physical Review B 106.16 (2022): L161107.