Pure Spin Currents
Experimental physicist Prof. Dr. Sebastian Goennenwein reported on his research in his lecture "Pure Spin Currents" on December 08, 2020.
Pure spin currents - i.e. directed motions of magnetic angular momentum - have only been experimentally accessible for a few years. In solids, pure spin currents can be generated, for example, by spin pumping in ferromagnet/normal metal heterostructures or by applying thermal gradients in the so-called spin Seebeck effect. The inverse spin Hall effect then lends itself to the detection of spin currents: Due to spin-orbit coupling, a spin current in certain materials also induces a charge current, which can then be detected with conventional electronics.
In the talk, an introduction or overview of the experimental investigation of pure spin currents was given. To this end, some basic concepts for spin transport were first introduced, and the conversion of charge currents to spin currents was discussed using the spin Hall effect. The main part of the talk then dealt with two key experiments on spin current transport, illustrating how pure spin currents can be generated, manipulated and measured. Finally, typical measurement setups and laboratory equipment were explained.