Parallelization and Visualization of Computational Nanotechnology LCAO Method
J C. Franiatte, Steven G. Satterfield, Garnett W. Bryant, J E. Devaney
Accurate atomic-scale quantum theory of nanostructures and nanosystems fabricated from nanostructures enables precision metrology of these nanosystems and provides the predictive, precision modeling tools needed for engineering these systems for applications including advanced semiconductor lasers and detectors, single photon sources and detectors, biosensors, and nanoarchitectures for quantum coherent technologies such as quantum computing. The tight-binding model based upon the Linear Combination of Atomic Orbitals (LCAO) method provides an atomistic theory for nanostructures which is accurate and easy to implement(1). The tight-binding method is ideal for modeling small nanostructures. However, the method becomes impractical to use on sequential computers, due to long run times, for modeling nanostructures with more than 25,000 atoms. Dramatic improvements in run time can be achieved through parallelization. We parallelize this method by dividing the structure into layers. Communication is across layers. First we create the structure. Then we solve the Hamiltonian equation for each atom considering only nearest neighbors using PARPACK(2). This parallel implementation is nearly linear in time. The output of the code is transferred to the NIST immersive environment where we study the structure interactively. This provides us with a detailed inspection and visualization of the structures and the atomic scale variation of calculated nanostructure properties that is not possible with any static graphical representation. We save the interaction with the structure in the immersive environment as a quicktime movie. The parallel implementation can handle arbitrary nanostructure shapes through an input file specification procedure. Structures of up to one million atoms are currently being studied.(1) G. W. Bryant and W. Jaskolski, Physica E 11, 72 (2001).(2) K. Maschhoff, D. Sorensen, A portable implementation of ARPACK for distributed memory parallel architectures, Preliminary proceedings, Copper Mountain Conference on Iterative Methods, 1996.
Proceedings of the Nanotechnology at the Interface of Information Technology Conference 2002
February 7-9, 2002
Conference on Nanotechnology at the Interface of Information Technology
, Satterfield, S.
, Bryant, G.
and Devaney, J.
Parallelization and Visualization of Computational Nanotechnology LCAO Method, Proceedings of the Nanotechnology at the Interface of Information Technology Conference 2002
(Accessed October 1, 2022)