Phase field modeling of phase patterns and domain structures in functional nano-composite films

本研究的目的是发展一套可用于分析和设计具有纳米复合自组装结构的薄膜的计算模型。自组装纳米复合膜是一类具有独特性能的新型材料。不同类型的此类薄膜可以具有不同的特殊性能：其中一些可以用作具有非常高的抗断裂性的超硬涂层，而另一些可以提供独特的电或磁性能。存在这样的系统，其中具有铁磁和铁电(铁电材料可以类似于保持磁化的铁磁材料)属性的组件之间的相互作用可以产生在各个组件中不能获得的效果，例如对电场的磁响应或对磁场的电响应。具有独特性能的不同组合的薄膜可以在广泛的不同应用中使用。自组装纳米复合膜结构中不同组分形成的图案对组分间以及膜与衬底之间的弹性相互作用很敏感。通过控制影响弹性相互作用的不同因素来控制这种模式是可能的。这项研究的第一个目标是开发一个计算模型，可以预测在什么条件下可以产生纳米复合材料结构中的不同类型的图案。有关模式的信息很重要，因为不同的模式会产生不同的属性。研究的第二部分将解决纳米复合材料中的成分图案与其电和/或磁性能之间的关系的问题。域结构的模型将允许我们预测不同模式的功能行为之间的差异。总之，开发的计算模型将使我们能够预测在什么条件下可以产生具有最佳性能的薄膜。

The purpose of the proposed research is to develop a set of computational models that can be used for the analysis and design of thin films with nano-composite self-assembling structures. The self-assembling nano-composite films are a new group of materials with unique properties. Different types of such films can have different special properties: some of them can be used as ultra hard coatings with a very high fracture resistance, while others can provide unique electrical or magnetic properties. There are systems wherein the interaction between the components with ferromagnetic and ferroelectric (a ferroelectric material can maintain electric polarization similarly to a ferromagnetic material maintaining magnetization) properties can produce effects that cannot be obtained in individual components, such as a magnetic response to an electric field or an electric response to a magnetic field. Thin films with different combinations of unique properties can be used in a wide range of different applications. The pattern formed by different components in the structure of a self-assembling nano-composite film is sensitive to elastic interactions between components and between the film and substrate. It is possible to control this pattern by controlling different factors affecting elastic interactions. The first goal of this research is to develop a computational model that can predict the conditions under which different types of patterns in the structure of nano-composites can be produced. The information about the pattern is important because different patterns will produce different properties. The second part of the research will address the problem of the relationship between the component pattern in a nano-composite and its electric and/or magnetic properties. Models of the domain structure will allow us to predict the difference between the functional behavior of different patterns. Together the developed computational models will allow us to predict the conditions under which thin films with the optimum properties can be produced.