SEMINAR: Magnonics � wave control on the nanoscale in metals and insulators

Periodically nanopatterned thin-film ferromagnets have been shown to form magnonic grating couplers [1] and magnonic crystals (MCs) [2], i.e., artificial crystals exhibiting tailored band structures for spin waves (magnons). In the GHz frequency regime, spin waves (SWs) are excited with wave lengths that are shorter by a few orders of magnitude compared to electromagnetic waves at the same frequency. At the same time unit cells of periodic magnetic lattices can exhibit different non-volatile remanent configurations, leading to both reconfigurable band structures [3] and metamaterials properties for SWs [4]. Such characteristics are not known from photonics or plasmonics. Nanostructured ferromagnets thereby represent an advanced approach for wave control in solid-state devices. Control and manipulaton of SWs for information transmission and processing on the nanoscale are now at the heart of the research field called ‘magnonics’. The modest SW damping in metallic ferromagnets used so far is however detrimental for possible applications. Insulating magnets might allow one to overcome the damping problem. In the talk we discuss and compare our recent results in magnonics based on metallic and insulating thin films. Parts of the research have received funding from the European Community’s Seventh Framework Programme (FP7/2007-2013) under Grant Agreement No. 228673 MAGNONICS and No. 247556 NoWaPhen, the DFG project GR1640/5-1 in SPP 1538 and the German Excellence Cluster ”Nanosystems Initiative Munich (NIM)”. [1] H. Yu, G. Duerr, R. Huber, M. Bahr, T. Schwarze, F. Brandl, and D. Grundler, Nature Commun. 4, 2702 (2013) [2] S. A. Nikitov, P. Tailhades, and C. S. Tsai, J. Magn. Magn. Mater. 236, 320 (2001) [3] J. Topp, D. Heitmann, M. Kostylev, and D. Grundler, Phys. Rev. Lett. 104, 207205 (2010) [4] R. Huber, M. Krawczyk, T. Schwarze, H. Yu, G. Duerr, S. Albert, and D. Grundler, Appl. Phys. Lett. 102, 012403 (2013)