Dislocation Core and Cross Slip Properties in Metals and Intermetallics: Linking ab initio and Continuum Approaches

摘要

This document has three parts. (1) Developed, tested, and implemented a novel concurrent multiscale approach which improves the coupling-quality between the quantum and the classical atomistic regions. This approach, which allows for the first time the study of the dislocation core structure and the effect of chemistry (impurities) on the dislocation core, was applied successfully to aluminum. (2) Developed and applied a novel sequential multiscale approach which couples ab initio and continuum approaches to study the dislocation core and cross-slip properties of nano-layered Cu-Ni multilayered thin films; and the effect of twinning in fcc metals. (3) Studied the spin transport in magnetic tunnel junctions and its anomalous bias dependence; and (4) Studied the effect of electron-phonon interaction in strongly correlated electron clusters on the interplay between the Kondo and magnetic ordering effect.