Event Date and Time
Dr. Satoru Emori, Virginia Tech
Minimizing magnetic damping is crucial for engineering spintronic devices (e.g., nanoscale magnetic memories and signal generators) that can be operated with low power input. However, the mechanisms of damping in various materials – even in the simplest ferromagnetic metals – have yet to be understood. In this talk, I will present our recent experiment that provides fundamental insight into magnetic damping in a simple model system: epitaxial thin films of pure Fe. We find that damping at room temperature is insensitive to the crystalline quality of epitaxial Fe (i.e., coherently strained vs. partially relaxed), although at low temperature higher crystalline quality leads to significantly higher damping. Our results show that damping is related to electrical conductivity in a way that cannot be explained by classical eddy current loss, thus pointing to intraband scattering as a key mechanism of damping. Our findings yield hints for engineering low-damping materials for power-efficient spintronic devices. Bio: Satoru Emori is an Assistant Professor in the Department of Physics at Virginia Tech. He received his B.S. in Materials Science and Engineering at the University of California, Irvine in 2008 and Ph.D. in Materials Science and Engineering at the Massachusetts Institute of Technology in 2013. His doctoral thesis work investigated the motion of chiral domain walls in ultrathin metallic ferromagnets. Following his postdoctoral work at Northeastern University and Stanford University, where he studied magnetization dynamics in complex oxide materials, he joined the faculty of Virginia Tech in Fall 2017. His new research group is focused on spin transport and dynamics in model thin-film materials, ranging from amorphous metals to epitaxial oxides.