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Title: Role of strain on electronic and mechanical response of semiconducting transition-metal dichalcogenide monolayers: An ab-initio study

Abstract

We characterize the electronic structure and elasticity of monolayer transition-metal dichalcogenides MX{sub 2} (M  =  Mo, W, Sn, Hf and X  =  S, Se, Te) based on 2H and 1T structures using fully relativistic first principles calculations based on density functional theory. We focus on the role of strain on the band structure and band alignment across the series of materials. We find that strain has a significant effect on the band gap; a biaxial strain of 1% decreases the band gap in the 2H structures, by as a much as 0.2  eV in MoS{sub 2} and WS{sub 2}, while increasing it for the 1T cases. These results indicate that strain is a powerful avenue to modulate their properties; for example, strain enables the formation of, otherwise impossible, broken gap heterostructures within the 2H class. These calculations provide insight and quantitative information for the rational development of heterostructures based on this class of materials accounting for the effect of strain.

Authors:
;  [1]
  1. School of Materials Engineering and Birck Nanotechnology Center, Purdue University, West Lafayette, Indiana 47907-2044 (United States)
Publication Date:
OSTI Identifier:
22304045
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 115; Journal Issue: 24; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; CHALCOGENIDES; COMPUTERIZED SIMULATION; DENSITY FUNCTIONAL METHOD; ELASTICITY; ELECTRONIC STRUCTURE; MOLYBDENUM SULFIDES; RELATIVISTIC RANGE; STRAINS; TRANSITION ELEMENT COMPOUNDS

Citation Formats

Guzman, David M., and Strachan, Alejandro, E-mail: strachan@purdue.edu. Role of strain on electronic and mechanical response of semiconducting transition-metal dichalcogenide monolayers: An ab-initio study. United States: N. p., 2014. Web. doi:10.1063/1.4883995.
Guzman, David M., & Strachan, Alejandro, E-mail: strachan@purdue.edu. Role of strain on electronic and mechanical response of semiconducting transition-metal dichalcogenide monolayers: An ab-initio study. United States. doi:10.1063/1.4883995.
Guzman, David M., and Strachan, Alejandro, E-mail: strachan@purdue.edu. Sat . "Role of strain on electronic and mechanical response of semiconducting transition-metal dichalcogenide monolayers: An ab-initio study". United States. doi:10.1063/1.4883995.
@article{osti_22304045,
title = {Role of strain on electronic and mechanical response of semiconducting transition-metal dichalcogenide monolayers: An ab-initio study},
author = {Guzman, David M. and Strachan, Alejandro, E-mail: strachan@purdue.edu},
abstractNote = {We characterize the electronic structure and elasticity of monolayer transition-metal dichalcogenides MX{sub 2} (M  =  Mo, W, Sn, Hf and X  =  S, Se, Te) based on 2H and 1T structures using fully relativistic first principles calculations based on density functional theory. We focus on the role of strain on the band structure and band alignment across the series of materials. We find that strain has a significant effect on the band gap; a biaxial strain of 1% decreases the band gap in the 2H structures, by as a much as 0.2  eV in MoS{sub 2} and WS{sub 2}, while increasing it for the 1T cases. These results indicate that strain is a powerful avenue to modulate their properties; for example, strain enables the formation of, otherwise impossible, broken gap heterostructures within the 2H class. These calculations provide insight and quantitative information for the rational development of heterostructures based on this class of materials accounting for the effect of strain.},
doi = {10.1063/1.4883995},
journal = {Journal of Applied Physics},
number = 24,
volume = 115,
place = {United States},
year = {Sat Jun 28 00:00:00 EDT 2014},
month = {Sat Jun 28 00:00:00 EDT 2014}
}
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