Spin current generation through acoustic wave injection - A path toward the development of new energy-saving electronic devices -



 A research group led by Ph. D. Student Ken-ichi Uchida and Professor Eiji Saitoh at Institute for Materials Research, Tohoku University has discovered a new method to generate spin current through acoustic wave injection.
  In recent years, more and more approaches to the environmental and energy issues have been taken, and it is required to develop clean and reliable energy sources and power-saving electronic devices. Spintronics, the new electronic technology which actively exploits spin freedom of electrons, is expected to develop novel drive principles of electric and magnetic devices and to save energy of them. Therefore, a lot of research on spintronics has been conducted all over the world. However, although most of the spintronics functions are driven by "spin current", the generation methods of spin current are very limited.
 In this study, we have discovered the new method to generate spin current only through the acoustic wave injection. This method enables us to extract electric and magnetic energy even from nonmagnetic insulators, which are used only as substrates of the devices. This achievement is expected to contribute the improvement of the degrees of freedom for spintronics device design and the development of next-generation energy-saving electronic technology with a very low impact on the environment.
 This research has been partly conducted in collaboration with Japan Atomic Energy Agency(JAEA), Graduate School of Engineering, Tohoku University and University of Keiserslautern (Germany), as part of the CREST program of JST.