Heterojunctions of model CdTe/CdSe mixtures

Journal Article · Wed Mar 18 00:00:00 EDT 2015 · Modelling and Simulation in Materials Science and Engineering

DOI:https://doi.org/10.1088/0965-0393/23/3/035007· OSTI ID:1145471

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

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

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.

• Research Organization: Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)
• Sponsoring Organization: USDOE; USDOE National Nuclear Security Administration (NNSA)
• Grant/Contract Number: AC04-94AL85000
• OSTI ID: 1145471
• Alternate ID(s): OSTI ID: 1239005; OSTI ID: 22539749
• Report Number(s): SAND--2014---4247J; 518364
• Journal Information: Modelling and Simulation in Materials Science and Engineering, Journal Name: Modelling and Simulation in Materials Science and Engineering Journal Issue: 3 Vol. 23; ISSN 0965-0393
• Publisher: IOP Publishing
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
Heterojunction
lattice mismatch
semiconductor