The advanced theoretical and experimental studies of spin wave phenomena were conducted in three areas: periodic magnonic structures, nonperiodic magnonic structures and on the interplay between magnonic and nonmagnetic phenomena in nanostructures.
In the first area, studies on damping of high frequency spin waves in nanostructures were conducted. We explored ways for minimization and optimization of the wave attenuation. We have developed theory of the exchange spin wave damping, which proved to be vital for high frequency spin waves in the curved waveguides and chiral textures. We designed the microwave response with nanopatterned magnonic structures with and without Dzyaloshinskii-Moriya interactions. We fabricated and performed extensive ferromagnetic resonance measurements of magnetic nanodots and antidots arranged in periodic lattices with the complex unit cells.
In the second area, we provided comprehensive theory of various forms of magnetic boundary conditions and their influence on the spin wave reflection, transmission and emission. The developed theory is crucial for experimental data analysis and design of the magnonic devices. We demonstrated theoretically influence the conditions at the film edge on the Goos-Haenchen shift of the spin waves. Further on, we showed the control of the transmitted wave phase by variation the properties at the interface. The property used for demonstration of the ultra-narrow metasurface for spin waves.
We achieved significant progress in developing models of the local spin wave excitation. We showed that any nonuniformity in a magnetic system, i.e. edge, magnetization texture, inhomogeneity of the field, can be a source of the spin waves. We demonstrated that propagation of the spin waves can be effectively controlled and enhanced by the gradual change of the magnetic parameters; with this we started new direction of research, called graded index magnonics.
We established fabrication procedure of the ultra-thin YIG films and demonstrated the large propagation length of GHz frequency spin waves, proving YIG being promising material for nanoscale magnonics. Based on the metallic ferromagnetic thin films we have demonstrated the principal properties of spin waves in quasicrystal structures, including multiple band gaps, localization and re-programmability.
In the area of the cross-disciplinary opportunities, we proposed and theoretically investigated 1D magnon-phononic (magphonic) crystals. We have developed a theory of longitudinal spin oscillations in ferromagnetic materials excited by ultrashort pulses of the laser light. The interesting feature is that the acoustic and exchange longitudinal spin oscillations have frequency higher than the transversal spin waves at the same wave vector.
The results obtained in the framework of the MagIC have been published in 117 scientific papers and presented in 210 presentations at international conferences. To strength the project visibility, we organized and co-organized 2nd and 3rd International Advanced School on Magnonics 2016 in Exeter, UK and 2018 in Kyiv, Ukraine, respectively, MagIC workshop in July 2017 near Poznan, and a special session devoted to magnonics during the Sol-Skymag conference in 2018 in San Sebastian, Spain.
