Heterojunctions of model CdTe/CdSe mixtures

van Swol, Frank; Zhou, Xiaowang W.; Challa, Sivakumar R.; Martin, James E.

doi:10.1088/0965-0393/23/3/035007

Title: Heterojunctions of model CdTe/CdSe mixtures

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Abstract

We report on the strain behavior of compound mixtures of model group II-VI semiconductors. We use the Stillinger-Weber Hamiltonian that we recently introduced, specifically developed to model binary mixtures of group II-VI compounds such as CdTe and CdSe. We also employ molecular dynamics simulations to examine the behavior of thin sheets of material, bilayers of CdTe and CdSe. The lattice mismatch between the two compounds leads to a strong bending of the entire sheet, with about a 0.5 to 1° deflection between neighboring planes. To further analyze bilayer bending, we introduce a simple one-dimensional model and use energy minimization to find the angle of deflection. The analysis is equivalent to a least-squares straight line fit. We consider the effects of bilayers which are asymmetric with respect to the thickness of the CdTe and CdSe parts. We thus learn that the bending can be subdivided into four kinds depending on the compressive/tensile nature of each outer plane of the sheet. We use this approach to directly compare our findings with experimental results on the bending of CdTe/CdSe rods. To reduce the effects of the lattice mismatch we explore diffuse interfaces, where we mix (i.e. alloy) Te and Se, and estimate themore » strain response.« less

Authors:

van Swol, Frank ^[1]; Zhou, Xiaowang W. ^[1]; Challa, Sivakumar R. ^[2]; Martin, James E. ^[1]

Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)
Univ. of New Mexico, Albuquerque, NM (United States)

Publication Date:: Wed Mar 18 00:00:00 EDT 2015

Research Org.:: Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

Sponsoring Org.:: USDOE National Nuclear Security Administration (NNSA)

OSTI Identifier:: 1145471

Alternate Identifier(s):: OSTI ID: 1239005

Report Number(s):: SAND-2014-4247J
Journal ID: ISSN 0965-0393; 518364

Grant/Contract Number:: AC04-94AL85000

Resource Type:: Accepted Manuscript

Journal Name:: Modelling and Simulation in Materials Science and Engineering

Additional Journal Information:: Journal Volume: 23; Journal Issue: 3; Journal ID: ISSN 0965-0393

Publisher:: IOP Publishing

Country of Publication:: United States

Language:: English

Subject:: 75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; 36 MATERIALS SCIENCE; Heterojunction; semiconductor; lattice mismatch

Citation Formats


                    van Swol, Frank, Zhou, Xiaowang W., Challa, Sivakumar R., and Martin, James E. Heterojunctions of model CdTe/CdSe mixtures.  United States: N. p., 2015. 
Web.  doi:10.1088/0965-0393/23/3/035007.

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                    van Swol, Frank, Zhou, Xiaowang W., Challa, Sivakumar R., & Martin, James E. Heterojunctions of model CdTe/CdSe mixtures.  United States.  https://doi.org/10.1088/0965-0393/23/3/035007

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                    van Swol, Frank, Zhou, Xiaowang W., Challa, Sivakumar R., and Martin, James E. Wed .  
"Heterojunctions of model CdTe/CdSe mixtures".  United States.  https://doi.org/10.1088/0965-0393/23/3/035007.  https://www.osti.gov/servlets/purl/1145471.

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@article{osti_1145471,

  title        = {Heterojunctions of model CdTe/CdSe mixtures},

  author       = {van Swol, Frank and Zhou, Xiaowang W. and Challa, Sivakumar R. and Martin, James E.},

  abstractNote = {We report on the strain behavior of compound mixtures of model group II-VI semiconductors. We use the Stillinger-Weber Hamiltonian that we recently introduced, specifically developed to model binary mixtures of group II-VI compounds such as CdTe and CdSe. We also employ molecular dynamics simulations to examine the behavior of thin sheets of material, bilayers of CdTe and CdSe. The lattice mismatch between the two compounds leads to a strong bending of the entire sheet, with about a 0.5 to 1° deflection between neighboring planes. To further analyze bilayer bending, we introduce a simple one-dimensional model and use energy minimization to find the angle of deflection. The analysis is equivalent to a least-squares straight line fit. We consider the effects of bilayers which are asymmetric with respect to the thickness of the CdTe and CdSe parts. We thus learn that the bending can be subdivided into four kinds depending on the compressive/tensile nature of each outer plane of the sheet. We use this approach to directly compare our findings with experimental results on the bending of CdTe/CdSe rods. To reduce the effects of the lattice mismatch we explore diffuse interfaces, where we mix (i.e. alloy) Te and Se, and estimate the strain response.},

  doi          = {10.1088/0965-0393/23/3/035007},

  journal      = {Modelling and Simulation in Materials Science and Engineering},

  number       = 3,

  volume       = 23,

  place        = {United States},

  year         = {Wed Mar 18 00:00:00 EDT 2015},

  month        = {Wed Mar 18 00:00:00 EDT 2015}

}

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