Spin Seebeck mechanical force

Harii, Kazuya; Seo, Y.-J.*; Tsutsumi, Yasumasa*; Chudo, Hiroyuki ; Oyanagi, Koichi*; Matsuo, Mamoru; Shiomi, Yuki*; Ono, Takahito*; Maekawa, Sadamichi; Saito, Eiji

Electric current has been used to send electricity to far distant places. On the other hand, spin current, a flow of electron spin, can in principle also send angular momentum to distant places. In a magnet, there is a universal spin carrier called a spin wave, a wave-type excitation of magnetization. Since spin waves exhibit a long propagation length, it should be able to send angular momentum that can generate torque and force at a distant place: a new function of magnets. Here we observe mechanical angular momentum transmission and force generation due to spin waves injected into YFeO by the spin-Seebeck effect. The spin-wave current, transmitted through a YFeO micro cantilever, was found to create a mechanical force on the cantilever as a non-local reaction of the spin-Seebeck effect. Spin-wave current can be generated remotely even in open circuits, and it can be used to drive micro mechanical devices.