Impact of Nanoscale Structure on Properties of Multiferroic Complex Oxides

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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.