"Microscopic theory of spin-orbit and spin-tranfer torques" 

Datum

10.02.2017

Zeit

11:00 - 13:00

Sprecher

Dr. Mikhail Titov

Sprache

en

Hauptthema

Chemie

Andere Themen

Chemie

Host

Prof. C. Felser; Dr. Fecher; Dr. Kreiner

Beschreibung

Spin-orbit and spin-transfer torques are competing forces that drive magnetic domains in the heavy-metal/ferromagnet bi-layers in the presence of electric current. In this talk I present a microscopic theory of both effects that is obtained from generalised Kubo formalism and avoids the notion of spin currents and spin Hall effect. In this formalism the torques are naturally related to susceptibility tensors that can be evaluated microscopically for a given model. In this talk I mainly focus on the torques arising in a heavy-metal/ferromagnet bilayers and demonstrate that spin-orbit interactions are generally responsible for a giant enhancement of spin transfer toques. Using the symmetry classification arising from the microscopic analysis I will also revise the existing classification of torques. In particular I distinguish three major spin-transfer torques in bi-layer systems. Finally I discuss the generalisations of the theory for torques in antiferromagnets and heterostructure involving Weyl semimetals and topological insulators.

Links

• MPI CPfS

Letztmalig verändert: 12.02.2017, 08:59:44