This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5).
NON-TECHNICAL DESCRIPTION: The recent discovery of a new iron-based family of high-temperature superconductors has generated tremendous interest in the scientific community. The discovery offers a new avenue for understanding the mechanism that gives rise to high-temperature superconductivity. The iron-based high-temperature superconductors are also of great interest for applications. For example, if the iron-based materials can be molded cost-efficiently into flexible wires, withstand high critical current densities and still be superconductors at liquid nitrogen temperatures, they offer the potential to transform the electrical power industry. In this program, the aim is to provide a framework in which mechanisms for superconductivity of the iron-based materials can be explored by using advanced methods of structural and electronic characterization combining state-of-the-art scanning transmission electron microscopes with state-of-the-art first-principles (parameter-free) calculations. The research program also includes training of a graduate student in the most advanced experimental methods and computational modeling to study materials at the atomic level. The training of students along both experimental and theoretical disciplines is a unique aspect of the proposed activity, and is expected to offer a wider range of career opportunities for the students in the current competitive job market. They plan to participate in outreach programs for high school teachers and students to develop high school lectures and hands-on teaching modules focused particularly in physics concepts that are directly applied in electron microscopy.
goal of this research program is to obtain a fundamental understanding of the electronic and atomic structure-property relationships in the recently discovered iron-based superconductors, using a combination of state-of-the-art experimental and computational modeling techniques. They propose to achieve this goal by investigating the atomic and electronic structures of the iron-based superconductors using atomic-resolution Z-contrast imaging, bright-field imaging and electron energy-loss spectroscopy (EELS) in an aberration-corrected scanning transmission electron microscope (STEM), total energy first-principles calculations based on density functional theory (DFT) and dynamical electron scattering (DES) calculations. They expect that this synergistic approach, where theory and experiment are equally emphasized, is going to have a significant and timely impact by providing, (i) a framework in which mechanisms for superconductivity of the iron-based materials can be explored, (ii) a detailed understanding at the atomic scale of the influence of defects on the macroscopic superconducting properties of the iron-based materials. The research program also includes training of a graduate student in the most advanced experimental methods and computational modeling to study materials at the atomic level. The training of students along both experimental and theoretical disciplines is a unique aspect of the proposed activity, and is expected to offer a wider range of career opportunities for the students in the current competitive job market. The methods and results of the research project proposed here will also be shared with high school students, further impacting the development and formation of students interested in and ready to pursue scientific research.
