Pietro Gambardella (ETH Zürich, Switzerland)

Date: Mon. September 7th, 2020, 12:45 pm-1:45 pm
Location: Zoom (ID: 941 5533 4256; for the passcode please contact the host Shulei Zhang: sxz675 at case.edu)
Website: https://intermag.mat.ethz.ch/

Charge-spin conversion effects and magnetization switching enabled by spin-orbit coupling

Pietro Gambardella

Department of Materials, ETH Zurich, CH – 8093 Zürich, Switzerland

Zoom Recording

The coupling of spin and orbital angular momenta underlies the magnetoelectric properties of matter. Although small, the spin-orbit interaction determines the preferred orientation of the order parameter in ferromagnets and antiferromagnets as well as the possibility to excite the magnetization out of equilibrium while ensuring the conservation of angular momentum. In recent years, advances in the understanding of the nonequilibrium charge-spin conversion processes mediated by the spin-orbit interaction have opened new perspectives for controlling the static and dynamic magnetization of all classes of magnetic materials, be they metallic or insulating, ferromagnetic or antiferromagnetic [1]. In this talk, I will review prominent mechanisms due to spin-orbit coupling that give rise to spin currents in magnetic heterostructures, showing how unusual magnetoresistance and spin torque phenomena emerge from charge-spin conversion in these materials. I will present results based on pump-probe magneto-optic experiments that allow us to measure the spin Hall effect in nonmagnetic conductors as well as current-induced switching of ferromagnets and ferrimagnets, and discuss emerging applications of so-called spin-orbit torque devices in magnetic random access memories.

[1] Current-induced spin-orbit torques in ferromagnetic and antiferromagnetic systems, A. Manchon, J. Železný, I.M. Miron, T. Jungwirth, J. Sinova, A. Thiaville, K. Garello, and P. Gambardella, Rev. Mod. Phys. 91, 035004 (2019).

Host: Shulei Zhang