RUI - Magnetic Symmetry and Symmetry Analysis of Domains

RUI - 磁对称性和域的对称性分析

• 批准号: 0074550
• 负责人: Daniel Litvin
• 金额: $ 12.95万
• 依托单位: Pennsylvania State Univ University Park
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2000
• 资助国家: 美国
• 起止时间: 2000-07-01 至 2004-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0074550&HistoricalAwards=false
• 关键词: RUI; Magnetic; Symmetry; Analysis; Domains

This is a grant for Research at Undergraduate Institutions (RUI). The understanding and prediction of the physical properties of domain structures which arise in a ferroic phase transition are based on an analysis of the properties and interrelationships of the associated crystallographic symmetries. To provide a basis for the classification of domain pairs and domain twins, the PI has derived and tabulated both the magnetic and non-magnetic subperiodic groups. This work will be continued and extended with a new tabulation of the magnetic space groups and a determination of the relationship between the magnetic space groups and magnetic subperiodic groups which is fundamental for the analysis of the relationship between domain structures and their domain walls.Also to be derived will be all of the magnetic twin laws, groups that express the symmetry relationships between two simultaneously observed magnetic domain states (domain pair) and are used to determine physical properties that can distinguish between the observed magnetic domains. The PI will also determine a classification of magnetic domain pairs where all domain pairs in a single class can be distinguished by the same set of physical property tensors, and determine in which ferroic phase transition such magnetic domain pairs arise. In the context of domain engineering the PI will classify sets of domain states, determining their symmetry and predicting their physical properties.Undergraduate students will participate in these research projects.%%%This is a grant for research at an undergraduate institution (RUI) which involves the participation of undergraduate students. The focus of the research is on tabulating and applying group theory to problems involving phase transitions in ferroelectrics. ***

这是本科院校研究补助金（RUI）。 对铁磁相变中出现的畴结构的物理性质的理解和预测是基于对相关晶体对称性的性质和相互关系的分析。 为了给畴对和畴孪晶的分类提供依据，PI推导并列出了磁性和非磁性亚周期群。 这一工作将继续下去，并将扩展到磁空间群的新列表，以及磁空间群和磁亚周期群之间的关系的确定，这是分析磁畴结构和它们的磁畴壁之间关系的基础。还将导出所有的磁孪晶定律，表示两个同时观察到的磁畴状态（磁畴对）之间的对称关系的组，并且用于确定可以区分观察到的磁畴的物理性质。 PI还将确定磁畴对的分类，其中单个类别中的所有磁畴对可以通过相同的物理性质张量集合来区分，并且确定在哪个铁性相变中出现这样的磁畴对。 在域工程的背景下，PI将对域状态进行分类，确定它们的对称性并预测它们的物理性质。本科生将参与这些研究项目。%这是一个研究在本科院校（RUI），涉及本科生的参与补助金。 研究的重点是列表和应用群论的问题，涉及铁电相变。***