Frequency-selective manipulation of spin waves: micromagnetic texture as amplitude valve and mode modulator

Spin-wave devices are regarded as one of the most promising candidates for future computation and data processing. How to manipulate spin-wave propagation is a key issue in realizing the functionality of these of devices. The existing manipulation methods have serious drawbacks for constructing practical spin-wave devices. Here, we propose an approach to harness the amplitude and mode excitation of traveling spin waves by introducing unique micromagnetic textures in a permalloy waveguide directly exchange-coupled to a pair of cobalt nanomagnets. We demonstrate that the imprinted micromagnetic textures, i.e., the 360 degrees domain wall and magnetic buckle, which play different roles in spin-wave manipulation, can be interchanged with each other repeatedly by using a sequence of homogeneous magnetic fields. Moreover, the suggested architecture could easily be tailored to implement fundamental logic-NOT operation. In light of the internal-field profile of the micromagnetic textures, speculation is offered concerning the physical origin underlying the observed spin-wave modulation phenomena.