电子科学与技术学院2017年学术报告会之五十四-Large scale quantum mechanical simulations of nanosystems
来源：电子科学与技术学院 浏览：2962 时间：2017-12-29
题目：Large scale quantum mechanical simulations of nanosystems
Simulations have played a more and more important role in material science research. In this talk, I will present the results using large scale super computers to simulate nanostructure systems. In particular, I will show how thousand atoms colloidal quantum dots can be calculated, including their optical properties and carrier dynamic behaviors. I will also discuss how the surface passivation of the nanocrystals can be calculated using ab initio method and how such calculations enhance our understanding of the surface physics of such systems, as well as the growth of such nanocrystals. Finally, I will show some results for the carrier dynamics of hybrid perovskite systems, and how the dynamics disorder of that system plays an important role for its carrier mobility.
Lin-Wang Wang: Senior Staff Scientist, Lawrence Berkeley National Laboratory, Berkeley, CA, U.S. Dr. Wang has 25 years of experience in large scale electronic structure calculations and methodology developments. He has worked in O(N) electronic structure calculations in early 1990s. He invented the folded spectrum method which pushed the limit of nonselfconsistent electronic structure calculations from 100 atoms to thousands of atoms. He developed a linear combination of bulk bands (LCBB) method for semiconductor heterostructrure electronic structure calculations, which allows the calculation of million atom devices. He developed generalized moments method which calculates the density of state and optical absorption spectra of a given system without explicit calculation of its eigenstates. He also developed a popular parallel total energy plane wave pseudopotential program (PEtot), which was later developed into the commercial code PWmat. He invented a charge patching method, which enables the ab initio accuracy thousand atom calculations for nanosystems. He has developed a linear scaling three dimensional fragment method (LS3DF), which can be used to selfconsistently calculate systems with tens of thousands of atoms. Recently, he developed a new algorithm for real-time time-dependent DFT calculations which accelerates the traditional algorithms by hundreds of times. He developed the Wannier Koopmans Method for DFT band gap calculations. He has also developed a transport calculation approach to calculate the scattering states based on plane wave nonlocal pseudopotentials. He has published 300 SCI papers, with a h-index of 67.