Mutual control of coherent spin waves and magnetic domain walls in a magnonic device.

The successful implementation of spin-wave devices requires efficient modulation of spin-wave propagation. Using cobalt/nickel multilayer films, we experimentally demonstrate that nanometer-wide magnetic domain walls can be applied to manipulate the phase and magnitude of coherent spin waves in a nonvolatile manner. We further show that a spin wave can, in turn, be used to change the position of magnetic domain walls by means of the spin-transfer torque effect generated from magnon spin current. This mutual interaction between spin waves and magnetic domain walls opens up the possibility of realizing all-magnon spintronic devices, in which one spin-wave signal can be used to control others by reconfiguring magnetic domain structures.