Generation of Spin Current by Acoustic Wave Spin Pumping
This success was achieved under the support of JST and by the collaboration among Tohoku University, JAEA, and Technische Universitaet Kaiserslautern in Germany. Details are published in Nature Materials.
Heat generation associated with electronic charge current will be problematic in future high-density electronics. Spin angular momentum, another entity of electron, is expected to carry information without heat generation. In contrast to existing methods of injecting spin current, such as electromagnetic waves, researchers have shown that acoustic waves, or phonons, can inject spin current by using a Ni81Fe19/Pt bilayer wire on an insulating sapphire plate.
Under a temperature gradient in the sapphire, the voltage generated in the Pt layer was shown to reflect the wire position, although the wire was insulated both electrically and magnetically. This non-local voltage is attributed to the coupling of spins and phonons generated by the temperature gradient, since phonons are the only possible carrier of information.
This is a demonstration of generating spin current by directly injecting acoustic waves to realize spin pumping. Researchers suggest that this finding will open the door to acoustic spintronics, in which acoustic waves are exploited for making spin-based devices.
Reference:
K. Uchida, H. Adachi, T. An, T. Ota, M. Toda, B. Hillebrands, S. Maekawa, and E. Saitoh, “Long-range spin Seebeck effect and acoustic spin pumping”, Nature Materials (2011) doi:10.1038/nmat3099
Media Contact
All latest news from the category: Materials Sciences
Materials management deals with the research, development, manufacturing and processing of raw and industrial materials. Key aspects here are biological and medical issues, which play an increasingly important role in this field.
innovations-report offers in-depth articles related to the development and application of materials and the structure and properties of new materials.
Newest articles
Superradiant atoms could push the boundaries of how precisely time can be measured
Superradiant atoms can help us measure time more precisely than ever. In a new study, researchers from the University of Copenhagen present a new method for measuring the time interval,…
Ion thermoelectric conversion devices for near room temperature
The electrode sheet of the thermoelectric device consists of ionic hydrogel, which is sandwiched between the electrodes to form, and the Prussian blue on the electrode undergoes a redox reaction…
Zap Energy achieves 37-million-degree temperatures in a compact device
New publication reports record electron temperatures for a small-scale, sheared-flow-stabilized Z-pinch fusion device. In the nine decades since humans first produced fusion reactions, only a few fusion technologies have demonstrated…