Physicists from Japan were able to transmit an electrical signal over a distance of one millimeter using a spin wave propagating in a dielectric.

The main task of spintronics is considered to be the study of the properties of spin-polarized currents. When such currents propagate in a conductor, information about the initial spin polarization is retained only at microscopic distances. Spin waves, on the other hand, can cover millimeter or even centimeter distances; it is this property that attracted the authors.

In the experiments, we used a magnetic dielectric plate Y₃Fe₅O₁₂ 1.3 μm thick, at both ends of which 15 nm thick platinum electrodes were placed at a distance of one millimeter from each other. When a current was passed through one of the electrodes, charge carriers with spin “up” and spin “down” deflected in different directions and accumulated at the opposite edges of the sample; electrons of one of the types appeared, thus, on the border between platinum and Y₃Fe₅O₁₂ … The reason for the spatial separation of electrons (the so-called spin Hall effect) is the spin-orbit interaction.

The obtained spin angular momentum was transferred by a spin wave in the bulk of the dielectric, and an excess of electrons with a certain spin projection was created on the adjacent surface of the second electrode. As a result, a potential difference arose – the signal transmission process ended.

The authors are currently experimenting with new material combinations in an effort to increase the transmission range.

Source: science.compulenta.ru