An Initio Study of Magnetoelectric Multiferroic Thin Films

技术概述：该奖项支持在磁电多铁性和薄膜铁电性领域最新进展的基础上进行的理论和计算研究，以设计和创造新型磁电多铁性，并了解它们在薄膜形式下的行为。PI旨在帮助阐明化学、有序性和应变之间的相互作用，以确定薄膜磁电多铁性的电子和磁性。有两个子项目：(I)通过利用成分反转对称破缺来设计新型薄膜多铁性材料，以将铁电性工程到其他非铁电磁性材料中。这一策略使PI能够绕过传统的铁电机制和磁性的存在之间的禁忌。(Ii)应变对多铁性铁电行为的影响的测定。PI的目标是识别或设计多铁性，在这些多铁性中，可以利用应变来增强极化，或者可以避免极化的过度应变依赖。研究还将测试各种Beyond-LDA方法描述强关联磁性绝缘体的适当性。该奖项还支持延长在以前的信息技术研究奖下开发的基于访问网格的高年级本科生/研究生水平的磁学和磁性材料网络课程。在一项相关的外展工作中，PI计划为五年级的材料化学教师开发一个动手课堂工具包，以解决加州科学标准中的主题。该奖项的网络基础设施方面包括：高级计算研究、网络课程开发和有助于未来网络基础设施基础的基础材料研究。非技术概述：该奖项支持磁电多铁体的理论和计算研究。这些材料同时显示磁性和铁电性，也就是磁性的电学模拟，在同一阶段。PI的目的是利用理论和计算来设计和创造新型的磁电多铁材料，并了解它们在薄膜形式下的行为。这项研究将有助于阐明化学、有序性和应变之间的相互作用如何决定薄膜磁电多铁材料的电子和磁性。目前已知的多铁材料很少。它们在信息技术和下一代网络基础设施方面具有潜在的技术应用。除了拥有它们的母体铁磁体和铁电体的组合功能外，这两种现象之间的耦合开辟了新的器件范例，其中电子行为由磁场控制，磁行为由电场控制。与合成材料科学家和设备物理学家的密切合作，旨在确保这一理论工作、新材料的实验生长和表征以及将新发现的材料纳入设备之间的协同作用。该奖项还支持延长根据以前的信息技术研究奖开发的关于磁性和磁性材料的高级本科生/初级研究生水平的基于Access Grid的网络课程。在一项相关的外展工作中，PI计划为五年级的材料化学教师开发一个动手课堂工具包，以解决加州科学标准中的主题。该奖项的网络基础设施方面包括：高级计算研究、网络课程开发和有助于未来网络基础设施基础的基础材料研究。

TECHNICAL SUMMARY:This award supports theoretical and computational research that builds on recent advances in the fields of magnetoelectric multiferroics and thin film ferroelectrics, to design and create novel magnetoelectric multiferroics and understand their behavior in thin film form. The PI seeks to help elucidate the interplay between chemistry, ordering and strain in determining the electronic and magnetic properties of thin film magnetoelectric multiferroics. There are two sub-projects:(i) The design of novel thin film multiferroics by exploiting compositional inversion symmetrybreaking to engineer ferroelectricity into otherwise non-ferroelectric magnetic materials. This strategy enables the PI to circumvent the contraindication between the conventional mechanism for ferroelectricity and the existence of magnetism. (ii) The determination of the effects of strain on the ferroelectric behavior of multiferroics. The PI aims to identify or design multiferroics in which either, strain can be exploited to enhance the polarization, or excessive strain dependence of the polarization can be avoided.The research will also test the appropriateness of the various beyond-LDA approaches for describing strongly-correlated magnetic insulators.This award also supports the extension of a senior undergraduate / beginning graduate level Access Grid-based cyber course on Magnetism and magnetic materials developed under the previous Information Technology Research award. In an associated outreach effort, the PI plans to develop a hands-on classroom kit for teachers on Materials Chemistry for 5th Grade to address topics in the California Science Standards. The cyberinfrastructure aspects of this award include: advanced computational research, cyber course development, and fundamental materials research that contributes to the foundations of future cyberinfrastructure.NON-TECHNICAL SUMMARY:This award supports theoretical and computational research on magnetoelectric multiferroics. These are materials that simultaneously display magnetism and ferroelectricity, the electrical analog of magnetism, in the same phase. The PI aims to use theory and computation to design and create novel magnetoelectric multiferroic materials and understand their behavior in thin film form. The research will help to elucidate how the interplay between chemistry, ordering and strain determines the electronic and magnetic properties of thin film magnetoelectric multiferroics. Few multiferroic materials are currently known. They have potential technological applications in information technology and the next generation of cyberinfrastructure. In addition to possessing the combined functionalities of their parent ferromagnets and ferroelectrics, coupling between the two phenomena opens new device paradigms, in which electronic behavior is controlled by a magnetic field and magnetic behavior is controlled by an electric field. A strong collaboration with synthetic materials scientists and device physicists, aims to ensure synergy between this theoretical effort, the experimental growth and characterization of new materials, and the incorporation of newly discovered materials into devices. This award also supports the extension of a senior undergraduate / beginning graduate level Access Grid-based cyber course on Magnetism and magnetic materials developed under the previous Information Technology Research award. In an associated outreach effort, the PI plans to develop a hands-on classroom kit for teachers on Materials Chemistry for 5th Grade to address topics in the California Science Standards. The cyberinfrastructure aspects of this award include: advanced computational research, cyber course development, and fundamental materials research that contributes to the foundations of future cyberinfrastructure.