Impact of Nanoscale Structure on Properties of Multiferroic Complex Oxides

社会正在进入“大数据”时代，需要新的材料来实现高密度存储。六方稀土氧化物就是这种材料的例子，它可能会给存储行业带来革命性的变化。本研究旨在使这些氧化物在器件应用中得以使用。特别是，研究人员正在确定氧化物的原子结构，这对于合理设计具有可支持有用功能的原子结构的新材料至关重要。研究生和本科生参与所有层次的工作，包括样品制备，实验室和基于同步加速器的测量，建模，软件开发和数据分析。为纽瓦克地区高中生设计的为期七周的过渡金属氧化物制备和表征的夏季研究和教学计划正在继续进行，其中包括为期一周的高中教师研讨会，使他们能够将计划的组成部分应用到他们的实验室实验中。项目更广泛的影响和评估的整体整合由新泽西理工大学领导、教育和评估研究合作组织协调。拟议的研究和教育是新泽西理工学院、罗格斯大学、布鲁克海文国家实验室、阿贡国家实验室、橡树岭国家实验室和高中生SEED计划（美国化学学会）之间的合作。该项目训练学生详细的样品制备、分析和建模。【技术摘要】能够显著提高随机存储器密度的材料有可能彻底改变存储行业。六方RMnO3的配合氧化物（R=稀土，Y， Sc或In）表现出稳定的极化涡域，是这种材料的良好候选者。该体系的立方（钙钛矿）相表现出磁化和电极化的强耦合，可能实现在磁场下写入极化位元。这项研究有两个目标，旨在潜在地使这些氧化物在器件应用中使用。第一个目标的目的是确定涡旋域上RMnO3氧化物的原子结构。假设这些材料中原子结构的非平凡空间变化与涡旋域极化的变化有关。目前，单个域内的原子结构是未知的。在第二个目标中，我们将研究压力对钙钛矿RMnO3结构的影响。这些材料表现出自旋驱动的电极化，这种极化可以通过压力来增强。研究生和本科生参与所有层次的工作，包括样品制备，实验室和基于同步加速器的测量，建模，软件开发和数据分析。为纽瓦克地区高中生设计的为期七周的过渡金属氧化物制备和表征的夏季研究和教学计划，正在扩展到一个为期一周的高中教师研讨会，使他们能够将计划的组成部分应用到他们的实验室实验中。项目更广泛的影响和评估的整体整合由新泽西理工大学的领导、教育和评估研究合作组织（CLEAR）协调。外部评估和后续研究将由蒙特克莱尔州立大学的教育和人类服务研究与评估中心（CREEHS）进行。这项研究是新泽西理工学院、罗格斯大学、布鲁克海文国家实验室、阿贡国家实验室、橡树岭国家实验室和高中生SEED项目（美国化学学会）合作进行的。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

Non-Technical AbstractSociety is entering the era of "big data" where new materials are needed to enable high-density storage. Hexagonal rare earth oxides are examples of such materials which may revolutionize the storage industry. This research aims at enabling the use of these oxides in device applications. In particular, the researchers are determining the atomic structures of the oxides, essential to rational designs of new materials with atomic structures that can support useful functionalities. Graduate and undergraduate students are involved in all levels of this work including sample preparation, laboratory and synchrotron-based measurements, modeling, software development and data analysis. A seven-week summer research and teaching program on transition metal oxide preparation and characterization, designed for Newark area high school students is being continued and includes a one-week workshop for high school teachers to enable them to implement components of the program into their laboratory experiments. Overall integration of the broader impacts and assessment of the project is coordinated by the Collaborative for Leadership, Education, and Assessment Research at NJIT. The proposed research and education is a collaboration between the New Jersey Institute of Technology, Rutgers University, Brookhaven National Laboratory, Argonne National Laboratory, Oak Ridge National Laboratory and the SEED program for high school students (American Chemical Society). The project is training students in detailed sample preparation, analysis, and modeling. Technical AbstractMaterials that can significantly increase the density of random access memory have the potential to revolutionize the storage industry. Complex oxides of hexagonal RMnO3 (R=Rare earth, Y, Sc or In) are good candidates for such materials as they exhibit stable polarization vortex domains. The cubic (perovskite) phase of this system shows strong coupling of magnetization and electric polarization possibly enabling writing of polarization bits with magnetic fields. This research has two objectives aimed at potentially enabling use of these oxides in device applications. The aim of the first objective is to determine the atomic structure of RMnO3 oxides across vortex domains. It is hypothesized that nontrivial spatial variations in atomic structure in these materials are related to changes in polarization across vortex domains. Currently, the atomic structures within individual domains are unknown. In the second objective, we will study effects of pressure on the structure of perovskite RMnO3. These materials exhibit spin-driven electric polarization which may be enhanced by pressure. Graduate and undergraduate students are involved in all levels of this work including sample preparation, laboratory and synchrotron-based measurements, modeling, software development and data analysis. A seven-week summer research and teaching program on transition metal oxide preparation and characterization, designed for Newark area high school students, is being extended to include a one-week workshop for high school teachers to enable them to implement components of the program into their laboratory experiments. Overall integration of the broader impacts and assessment of the project is coordinated by the Collaborative for Leadership, Education, and Assessment Research (CLEAR) at NJIT. External assessment and follow-on studies will be conducted by the Center for Research and Evaluation on Education and Human Services (CREEHS) at Montclair State University. The research is a collaboration between the New Jersey Institute of Technology, Rutgers University, Brookhaven National Laboratory, Argonne National Laboratory, Oak Ridge National Laboratory and the SEED program for high school students (American Chemical Society).This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.