IMSE Seminar with Lin Zhou on Magnetic Materials and Electron Microscopy
The properties of materials are dictated by their internal atom arrangement. Advanced electron microscopy techniques, such as (scanning) transmission electron microscopy, with its many different operation modes for imaging, diffraction, and spectroscopy, have become indispensable for simultaneous structure, chemistry, and internal magnetic/electric/strain field probing down to the atomic level. Increasingly sophisticated specimen holders that can expose materials to external stimuli (thermal, stress/strain, electric, and magnetic) during imaging, expanding electron-beam techniques from characterizing materials in 3D to 4D studies that include spatial and temporal aspects. In this presentation, various electron beam microscopy techniques have been used separately or in tandem in our collaborative studies to 1) enhance coercivity of alnico permanent magnets, 2) reveal formation mechanism and dynamics of magnetic skyrmion lattices, and 3) understand interface structure that causes coherence loss in superconducting qubits. Through these examples, we will illustrate how electron microscopy has enabled the development of materials and, conversely, how investigating the structure and behavior of the most challenging materials helps to advance the state of the art in electron microscopy.
Dr. Lin Zhou is a Staff Scientist in Ames National Laboratory and an associate professor in the Materials Science and Engineering Department at Iowa State University. Dr. Zhou obtained her Ph.D. degree in Materials Science and Engineering from Arizona State University in 2006. Her research focuses on developing and applying advanced electron microscopy techniques to study the material structure-property relationship and discover mechanisms and dynamics of phase transitions. She has published more than 100 peer-reviewed journal papers. She is the Group Leader and Science Coordinator of the Sensitive Instrument Facility in Ames National Laboratory. She also serves as a lead team member in the material focus area in DOE’s multi-institution Superconducting Quantum Materials and Systems Center (SQMS), led by Fermi National Lab.
Faculty, students, and the general public are invited.