Predicting the Electronic Properties of 3D, Million-Atom Semiconductor Nanostructure Architectures
Revolutionary breakthroughs in quantum dots
First, that the dots exhibiting clean and rich spectroscopic and transport characteristics are rather big. Indeed, the phenomenology indicated above is exhibited only by the well-passivated defect-free quantum dots containing at least a few thousand atoms (colloidal) and even a few hundred thousand atoms (self assembled). Understanding the behavior of nanotechnology devices requires the study of even larger, million-atom systems composed of multiple components such as wires+dots+films.
Second, first-principles
many-body computational techniques based on current approaches (Quantum Monte-Carlo, GW, Bethe-Salpeter)
are unlikely to be adaptable to such large structures and, at the same time, the effective mass-based
techniques are too crude to provide insights on the many-body/atomistic phenomenology revealed by experiment.
Thus, we have developed a set of methods that use an atomistic approach (unlike effective-mass based techniques)
and utilize single-particle + many body techniques that are readily scalable to ~103-106 atom nanostructures.
- A. Zunger, A. Franceschetti, G. Bester, Materials Science Center, NREL.
- W.B. Jones, Kwiseon Kim and P. A. Graf, Scientific Computing Center, NREL.
- L-W. Wang, A. Canning, O. Marques, C. Voemel, Computational Research Division, LBNL.
- J. Dongarra, J. Langou and S. Tomov, Dept. of Computer Science, University of Tennessee.