Band structure of molybdenum disulfide: from first principle to analytical band model

TL;DR

This paper introduces an analytical band calculation (ABC) model for monolayer molybdenum disulfide that accurately captures its band structure across energy ranges, improving upon the effective mass approximation.

Contribution

The paper develops and validates an analytical band model fitted to first-principles data, enabling precise calculations of electronic properties in 2D materials.

Findings

ABC model accurately fits first-principles band structure

Model effectively calculates density of states and group velocity

Potential for analyzing ballistic transport in 2D semiconductors

Abstract

A simple band model such as the effective mass approximation (EMA) can be used to quickly obtain the lower-energy region for the band structure of monolayer molybdenum disulfide. But the EMA band model cannot give the correct description for the band structure in the higher-energy region. To address this major issue, we propose an analytical band calculation (ABC) model to study monolayer molybdenum disulfide. Important parameters of the ABC model are obtained by fitting the three-direction band structure of monolayer molybdenum disulfide obtained from the first-principles (FP) method. The proposed ABC model fits well with the FP band structure calculation result for monolayer molybdenum disulfide. We also use the ABC model to calculate physical quantities used in carrier transport such as density of states and group velocity. Our ABC model can be extended and further utilized for calculating the key physical quantities of ballistic transport of 2D semiconductor materials.