Efficient modeling techniques for atomistic-based electronic density calculations

摘要

This paper presents an effective combination of various modeling and numerical techniques for enabling fast large-scale first-principle electronic density calculations. A real-space mesh technique framework is used to discretized the DFT/Kohn-Sham equations in the entire 3D atomistic system, then a mode decomposition approach is proposed to reduce the size and the bandwidth of the obtained system matrix. The electron density is computed by performing the contour integration of the mode Green's function along the complex energy plane using a O(N) diagonal banded system solver. Finally, we present and discuss the performance results of the proposed ab-initio atomistic-based electronic density calculations with application to Carbon nanotube (CNT).