Dominant Role of Sulphur divacancy in Charge Trapping Dynamics in MoS$_2$

Fuente: arXiv
Salvato in:
Dettagli Bibliografici
Autori principali: Somay, Srest, Bhattacharya, Sitangshu, Balasubramanian, Krishna
Natura: Preprint
Pubblicazione: 2026
Soggetti:
Accesso online:
Tags: Aggiungi Tag
Nessun Tag, puoi essere il primo ad aggiungerne!!
_version_ 1866918488169250816
author Somay, Srest
Bhattacharya, Sitangshu
Balasubramanian, Krishna
author_facet Somay, Srest
Bhattacharya, Sitangshu
Balasubramanian, Krishna
contents Intrinsic defects govern carrier trapping and recombination in two-dimensional semiconductors, yet the microscopic origin of defect-dependent capture dynamics remains unclear. Here, we compute carrier capture coefficients of vacancy defects, treating monolayer MoS$_2$ as a prototype, from first principles. We find that the single Sulphur vacancy forms a shallow defect with a small capture coefficient of $\sim 10^{-16}\ \mathrm{cm}^3/\mathrm{s}$, whereas the Sulphur divacancy exhibits a capture coefficient larger by seven orders of magnitude, $\sim 10^{-9}\ \mathrm{cm}^3/\mathrm{s}$, despite being only moderately deeper in energy. This enhancement originates from strong lattice relaxation enabling efficient multiphonon capture. Consequently, single vacancies contribute weakly to trapping, while Sulphur divacancies dominate nonradiative recombination and reduce quantum yield. In contrast, molybdenum vacancies and Sulphur antisites, although deep, show much smaller capture coefficients, indicating a limited role in carrier trapping in n-type devices.
format Preprint
id arxiv_https___arxiv_org_abs_2605_06109
institution arXiv
publishDate 2026
record_format arxiv
spellingShingle Dominant Role of Sulphur divacancy in Charge Trapping Dynamics in MoS$_2$
Somay, Srest
Bhattacharya, Sitangshu
Balasubramanian, Krishna
Strongly Correlated Electrons
Intrinsic defects govern carrier trapping and recombination in two-dimensional semiconductors, yet the microscopic origin of defect-dependent capture dynamics remains unclear. Here, we compute carrier capture coefficients of vacancy defects, treating monolayer MoS$_2$ as a prototype, from first principles. We find that the single Sulphur vacancy forms a shallow defect with a small capture coefficient of $\sim 10^{-16}\ \mathrm{cm}^3/\mathrm{s}$, whereas the Sulphur divacancy exhibits a capture coefficient larger by seven orders of magnitude, $\sim 10^{-9}\ \mathrm{cm}^3/\mathrm{s}$, despite being only moderately deeper in energy. This enhancement originates from strong lattice relaxation enabling efficient multiphonon capture. Consequently, single vacancies contribute weakly to trapping, while Sulphur divacancies dominate nonradiative recombination and reduce quantum yield. In contrast, molybdenum vacancies and Sulphur antisites, although deep, show much smaller capture coefficients, indicating a limited role in carrier trapping in n-type devices.
title Dominant Role of Sulphur divacancy in Charge Trapping Dynamics in MoS$_2$
topic Strongly Correlated Electrons
url https://arxiv.org/abs/2605.06109