Predicting the Electronic Properties of 3D, Millionatom Semiconductor nanostructure Architectures
Abstract
This final report describes the work done by Jack Dongarra (University Distinguished Professor) and Stanimire Tomov (Research Scientist) related to the DOE project entitled Predicting the Electronic Properties of 3D, MillionAtom Semiconductor Nanostructure Architectures. In this project we addressed the mathematical methodology required to calculate the electronic and transport properties of large nanostructures with comparable accuracy and reliability to that of current ab initio methods. This capability is critical for further developing the field, yet it is missing in all the existing computational methods. Additionally, quantitative comparisons with experiments are often needed for a qualitative understanding of the physics, and for guiding the design of new nanostructures. We focused on the mathematical challenges of the project, in particular on solvers and preconditioners for large scale eigenvalue problems that occur in the computation of electronic states of large nanosystems. Usually, the states of interest lie in the interior of the spectrum and their computation poses great difficulties for existing algorithms. The electronic properties of a semiconductor nanostructure architecture can be predicted/determined by computing its band structure. Of particular importance are the 'band edge states' (electronic states near the energy gap) which can be computed from a properly defined interior eigenvalue problem.more »
 Authors:
 Publication Date:
 Research Org.:
 Univ. of Tennessee, Knoxville, TN (United States)
 Sponsoring Org.:
 USDOE SC Office of Advanced Scientific Computing Research (SC21); USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC22)
 OSTI Identifier:
 1036499
 Report Number(s):
 DOE/ER255845
TRN: US201208%%869
 DOE Contract Number:
 FG0203ER25584
 Resource Type:
 Technical Report
 Country of Publication:
 United States
 Language:
 English
 Subject:
 77 NANOSCIENCE AND NANOTECHNOLOGY; ACCURACY; ALGORITHMS; ARCHITECTURE; DESIGN; EIGENVALUES; ENERGY GAP; NANOSTRUCTURES; PHYSICS; RELIABILITY; TRANSPORT; computational nanotechnology; electronic structure; preconditioned conjugate gradients; bulk band; quantum dots; parallel eigenvalue solvers; block method
Citation Formats
Jack Dongarra, and Stanimire Tomov. Predicting the Electronic Properties of 3D, Millionatom Semiconductor nanostructure Architectures. United States: N. p., 2012.
Web. doi:10.2172/1036499.
Jack Dongarra, & Stanimire Tomov. Predicting the Electronic Properties of 3D, Millionatom Semiconductor nanostructure Architectures. United States. doi:10.2172/1036499.
Jack Dongarra, and Stanimire Tomov. 2012.
"Predicting the Electronic Properties of 3D, Millionatom Semiconductor nanostructure Architectures". United States.
doi:10.2172/1036499. https://www.osti.gov/servlets/purl/1036499.
@article{osti_1036499,
title = {Predicting the Electronic Properties of 3D, Millionatom Semiconductor nanostructure Architectures},
author = {Jack Dongarra and Stanimire Tomov},
abstractNote = {This final report describes the work done by Jack Dongarra (University Distinguished Professor) and Stanimire Tomov (Research Scientist) related to the DOE project entitled Predicting the Electronic Properties of 3D, MillionAtom Semiconductor Nanostructure Architectures. In this project we addressed the mathematical methodology required to calculate the electronic and transport properties of large nanostructures with comparable accuracy and reliability to that of current ab initio methods. This capability is critical for further developing the field, yet it is missing in all the existing computational methods. Additionally, quantitative comparisons with experiments are often needed for a qualitative understanding of the physics, and for guiding the design of new nanostructures. We focused on the mathematical challenges of the project, in particular on solvers and preconditioners for large scale eigenvalue problems that occur in the computation of electronic states of large nanosystems. Usually, the states of interest lie in the interior of the spectrum and their computation poses great difficulties for existing algorithms. The electronic properties of a semiconductor nanostructure architecture can be predicted/determined by computing its band structure. Of particular importance are the 'band edge states' (electronic states near the energy gap) which can be computed from a properly defined interior eigenvalue problem. Our primary mathematics and computational challenge here has been to develop an efficient solution methodology for finding these interior states for very large systems. Our work has produced excellent results in terms of developing both new and extending current stateoftheart techniques.},
doi = {10.2172/1036499},
journal = {},
number = ,
volume = ,
place = {United States},
year = 2012,
month = 3
}

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