Speaker: Dr. Sergi Lendinez (Department of Physics and Astronomy, University of Delaware)

Title: Vortex motion excited by spin orbit torques

Abstract: Sergi Lendinez1, 2, Tomas Polakovic3, Junjia Ding2, Benjamin Jungfleisch1, John Pearson2, Axel Hoffmann2, Valentine Novosad2

1Department of Physics and Astronomy, University of Delaware, Newark, DE 197162Materials Science Division, Argonne National Laboratory, Argonne, IL 604393Physics Division, Argonne National Laboratory, Argonne, IL 60439

The development of new memory technologies requires a decrease in the current density and a better efficiency of the devices. Spin torque is a way to efficiently drive dynamics that shows potential for implementation in future devices. High frequency dynamics (in the range of tens of GHZ) have been intensively studied due to the high switching speeds in the ns range. Spin orbit torques, that can be achieved using simple fabrication structures, have been used mostly to excite these high frequency dynamics. However, lower frequency dynamics below 1 GHz are also interesting since in this frequency range magnetic domains and magnetic structures dominate the dynamics. In this talk, I will show that it is possible to observe low-frequency dynamics, in particular vortex gyrotropic motion, using spin orbit torques. Micromagnetic simulations support the dynamic spin torque measurements, as well as the magnetic transport measurements. Our results are of importance to integrate spin-orbit-torque to excite magnetic vortices in spintronic devices. Bio: Sergi Lendinez is a postdoctorate researcher in the Department of Physics and Astronomy at the University of Delaware. Before joining Prof. Jungfleisch's group, he was a postdoctoral appointee in the Magnetic Films Group in the Materials Science Division at Argonne National Laboratory. His work is in the field of magnetization dynamics in magnetic thin films and in patterned structures. The main focus of his work is on the study of propagation of spin waves in different media and possible applications in spintronic devices. Sergi received his PhD from the University of Barcelona, Spain. He did part of his PhD at Paul Drude Institute, Germany, and at Argonne National Laboratory.