Multi-physics Analysis of Nano-components by First-Principle Simulation

Abstract

In recent years, materials in a nano-scale such as nano-films, nano-wires, and nano-dots have been manufactured not only by scientific interest but also by anticipation of future practical application. They possess different characteristic strength from their macro-scale counterparts (effect of external structure; shape). On the other hand, it is well known that the understructure (e.g., grain boundary) affects the material strength. At atomic level, the crystallographic understructure means the distortion of atomic arrangement; grain boundary; e.g. domain wall. In order to understand the strength of nano-components, the both effects have to be clarified. Thus, we have investigated the mechanical behavior of nano-components by ab initio computational simulations1-3. The electrical (magnetic) property is never constant when materials are subjected to external load. This coupling effect between mechanical deformation and electrical properties is called the “multi-physics propertyâ€. Since this stems from the electronic structure at the atomic level, the external structure as well as the understructure in nano-components eminently influences the characteristics. The ab initio simulation is powerful tool to analyze the behavior as well2, 4-11. In the below, we show some examples on the ferro-electric behavior of PbTiO3 in nano-components5-