Statics and Dynamics of Spatially and Dimensionally Constrained Oxides

The natural evolution of functional oxides (e.g., Ferroelectric-FE and Ferrimagnetic-FM) calls for their confinement in spatial and dimensional modes in the form of nanopatterned architecture. Further, juxtaposing two or more FE/FM oxides in close-proximity provide exciting new opportunities for synergistic coupling. However, due to lack of truly nanoscale patterning approaches for oxides, it has not been hitherto possible to probe such confinement effects for FE and FM oxides. The proposed research will develop innovative methods for nanopatterning of FE/FM oxides, followed by in-situ and ex-situ characterization of the nanoscale confinement effects. The intellectual underpinning revolves around understanding of the decisive role of spatial and dimensional constraints on microstructure evolution, localized characteristics of interfaces, and size/shape-specific properties/phenomena in FE/FM oxides. The research will advance nanopatterning techniques (<100nm) for oxides, based on hybrid approaches which harness the established top-down approach (eBL) coupled to soft chemistry (sol-gel). It will address critical scientific issues associated with phase transformation (crystallization) under constraints, atomic structure of limited-length interfaces and coupled phenomena influenced by proximal spatial and dimensional constraints. The proposed work involves innovative in-situ 3-D tomographic structural (and chemical) reconstruction of various stages of microstructure evolution, atomic-scale structure, chemistry and electronic structural attributes of constrained oxide interfaces, as well as their localized and coupled FE/FM properties/phenomena. As a result, the proposed research sets the stage for meaningful theoretical/simulation/modeling of nanopatterned oxides, anchored by extensive experimental analysis. Both, ex-situ and in-situ dynamic studies (with S/TEM, synchrotron x-ray scattering and SPM) are proposed, which provide high temporal and spatial resolution details of the dynamics of microstructure, associated interfaces and external shape architecture, with collaborative opportunities. The combination of innovative nanopatterned geometries and their in-situ, ex-situ and correlative characterization with synchrotron x-ray scattering, advanced microscopy and scanning probe analysis, will likely open new vistas for fundamental understanding of constrained oxide nanostructures and their potential applications. Proposed project will enable innovative class-room and hands-on training for researchers in the rapidly evolving field of nanopatterning, nanoscale oxides and their diverse applications. PI will include research as a part of several UG and graduate courses that he teaches at NU, including specific laboratory modules on eBL of proposed research and nanostructured ceramics in introductory course in ceramics. Two minority research interns will be hired by presenting such opportunities at UG societies (Women, Black and Hispanic UG Societies). PI serves on Provost Task Force to enhance minority student enrollment at UG and graduate levels, and has contributed to successful minority recruiting efforts at NU. PI will incorporate research findings in his frequent Town Hall meetings/presentations in Nanoscience/Nanotechnology to local communities. As the director of the characterization and instrumentation facility, the NUANCE Center, PI is actively engaged with outreach to local Chicago area museums; including Art Institute of Chicago (for characterization of work of art), Field Museum of Chicago (analysis of artifacts) and the C