High-efficiency control of spin-wave propagation in ultra-thin yttrium iron garnet by the spin-orbit torque

We study experimentally with submicrometer spatial resolution the propagation of spin waves in microscopic waveguides based on the nanometer-thick yttrium iron garnet and Pt layers. We demonstrate that by using the spin-orbit torque, the propagation length of the spin waves in such systems can be increased by nearly a factor of 10, which corresponds to the increase in the spin-wave intensity at the output of a 10 μm long transmission line by three orders of magnitude. We also show that, in the regime, where the magnetic damping is completely compensated by the spin-orbit torque, the spin-wave amplification is suppressed by the nonlinear scattering of the coherent spin waves from current-induced excitations.This research was partially supported by the Deutsche Forschungsgemeinschaft, the ANR Grant Trinidad (ASTRID 2012 Program), and the program Megagrant No. 14.Z50.31.0025 of the Russian Ministry of Education and Science. M.C. acknowledges DGA for the financial support. V.V.N. acknowledges the support from the Competitive Growth of KFU.Peer reviewe