HMC Physics Colloquium

Tuesdays at 16:30 in Shanahan Center for Teaching and Learning, Room B460

Alex Frañó

University of California at San Diego

The “quantumness” of quantum materials explored by resonant x-ray scattering

April 23, 2019

We are in exciting times for synchrotron science and condensed matter physics. Modern x-ray experiments offer a powerful tool to address fundamental questions about materials. In this colloquium, I will illustrate some intriguing cases involving materials in which electronic correlations yield intertwined, ordered patterns of the spin, charge and orbital character of the wave functions. I will discuss x-ray scattering methods which are key to investigate the interplay of such “quantum periodicities”, which turn out to be very important in governing the macroscopic physics. I will overview the recent discovery of charge ordering as a potentially crucial ingredient in high temperature superconductivity. Furthermore, exploiting the high cross-section and element specificity of resonant scattering, magnetism solely at interfaces between oxide layers can now be detected. In addition, applied magnetic fields can expose momentum-resolved coexistence of various magnetic phases in frustrated Kitaev systems. Finally, I will discuss far-reaching changes that are occurring in synchrotron facilities which will shape our research field throughout the next decades.