Event Information |
MSE Seminar: Dr. Ismail El Baggari, Harvard University Cryogenic Electron Microscopy of Quantum Matter Abstract: Quantum-mechanical effects and strong electron-electron interactions give rise to solids with superb electronic properties and a vast potential for future technologies. In many of these strongly interacting materials, electrons self-organize into new spatial patterns that break the symmetry of the underlying crystal. A grand challenge in the field is to understand the nature of these symmetry-breaking states and to overcome their tendency to form inhomogeneous textures at the nanoscale. Towards that goal, atomic-resolution transmission electron microscopy techniques hold immense promise for advancing quantum materials research; however, progress has been hindered by the lack of low-temperature capabilities that are necessary to study quantum systems. Here I will show vivid atomic-scale visualizations of electronic order in strongly correlated oxides unleashed by the development of cryogenic scanning transmission electron microscopy (cryo-STEM). This novel technique enables direct visualizations of (i) the picoscale atomic displacements governing electronic transitions in quantum materials, (ii) the nature and symmetry of charge/orbital order, and (iii) a complex nanoscale landscape involving topological defects, phase competition, and inhomogeneity. Finally, I will describe our recent and unique approach that has enabled cryogenic electron microscopy with liquid helium cooling and atomic resolution. These capabilities pave the way for novel explorations of ultra-low temperature quantum phenomena in the electron microscope. Bio: Ismail El Baggari is a Principal Investigator and Fellow at the Rowland Institute at Harvard. He obtained his Ph.D. and M.S. in Physics from Cornell University working with the late Prof. Lena Kourkoutis and a Bachelor of Science in Applied Physics from Yale University. His research focuses on the development of in situ cryogenic electron microscopy for understanding quantum materials and devices. This Event is For: Graduate • Undergraduate • Faculty |