ABSTRACT
This chapter focuses on the design and realization of multidirectional microwave-to-magnon transducers that allow one to emit short-wavelength spin waves (SWs) with relatively large intensity in different spatial directions from conventional GHz antennas. It fabricates ferromagnetic structures whose magnetic properties are periodically modulated. Short-wavelength SWs are stimulated by an intrinsic magnonic grating coupler effect experimentally evidenced in different periodically patterned ferromagnetic material. The chapter outlines relevant fabrication steps to realize a magnonic grating coupler that is resonant and operated on yttrium iron garnet (YIG). It describes the spectroscopy technique and evaluates from corresponding spectra. The chapter summarizes experiments on two different types of grating couplers, that is, resonant and nonresonant couplers. Resist mesas are exposed and the YIG is etched in order to confine spin excitations to a specific region. At the same time, markers are prepared on the sample to align precisely the microwave-to-magnon transducers and coplanar waveguides (CPWs) prepared via electron-beam lithography at a later stage.
