Revealing Charge Transfer in Defect-Engineered 4H$_\mathrm{b}$-TaS$_2$

TL;DR

This study uses first-principles calculations to analyze over 90 defects in 4H_b-TaS_2, revealing their microscopic nature and impact on interlayer charge transfer, which influences exotic quantum phases.

Contribution

It provides a comprehensive dataset and analysis of defect types and their effects in 4H_b-TaS_2, advancing understanding of defect engineering in layered transition metal dichalcogenides.

Findings

Identified various defect types and their formation energies.

Demonstrated how defects influence charge transfer between layers.

Provided a resource for future defect engineering research.

Abstract

We present a comprehensive first-principles investigation of defects in 4$H_b$-TaS$_2$. In this layered transition metal dichalcogenide, charge transfer between alternating Mott-insulating 1T and metallic 1H layers gives rise to exotic quantum phases such as the Kondo effect and topological superconductivity. Motivated by recent defect manipulation in 4$H_b$-TaS$_2$ via STM, we address their microscopic nature and impact on interlayer charge transfer. To this end, we systematically analyze over 90 defects using large-scale density functional theory (DFT) calculations. Our extensive dataset, compiled from STM simulations, defect formation energies, work functions, and charge transfer, establishes a foundational resource for future theoretical and experimental studies on defect engineering in 4$H_b$-TaS$_2$.