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arXiv · 2205.02175

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

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.

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Cheng-Hsien Yang, Yun-Fang Chung, Yen-Shuo Su, Kuan-Ting Chen, Yi-Sheng Huang, Shu-Tong Chang. 2022-05-04. Band structure of molybdenum disulfide: from first principle to analytical band model. https://doi.org/10.1007/s10825-022-01880-2

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