When heat ceases to be a mystery, spintronics becomes more real

The development of spintronics depends on materials that guarantee control over the flow of magnetically polarized currents. However, it is hard to talk about control when the details of heat transport through the interfaces between materials are unknown. This thermal gap in our material knowledge has just been filled thanks to a Polish-German team of physicists, who now describe in detail the dynamic phenomena occurring at the interface between a ferromagnetic metal and a semiconductor.

Spintronics has been proposed as a successor of electronics. In spintronic devices, electric currents are replaced by spin currents. One promising material for this type of application seems to be a gallium arsenide/iron silicide heterostructure. For every four electrons passing through this interface, as many as three carry information about the direction of the magnetic moment. So far, however, little was known about the dynamic properties of the interface, which determine the heat flow. A collaboration between the Institute of Nuclear Physics of the Polish Academy of Sciences (IFJ PAN) in Cracow, the Karlsruhe Institute of Technology (KIT), the Paul Drude Institut für Festkörperelektronik in Berlin and the DESY research Centre in Hamburg has finally helped to close this gap.