Unidirectional spin-wave edge modes in magnonic crystal
J. Feilhauer,
M. Zelent,
Zhiwang Zhang,
J. Christensen,
M. Mruczkiewicz
Affiliations
J. Feilhauer
Institute of Electrical Engineering, Slovak Academy of Sciences, Dubravska Cesta 9, SK-841-04 Bratislava, Slovakia
M. Zelent
Faculty of Physics, Adam Mickiewicz University in Poznan, Umultowska 85, Poznan PL-61-614, Poland
Zhiwang Zhang
Department of Physics, MOE Key Laboratory of Modern Acoustics, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210093, China
J. Christensen
IMDEA Materials Institute, Calle Eric Kandel, 2, 28906 Getafe, Madrid, Spain
M. Mruczkiewicz
Institute of Electrical Engineering, Slovak Academy of Sciences, Dubravska Cesta 9, SK-841-04 Bratislava, Slovakia
We present a numerical demonstration of magnonic crystals hosting unidirectional, topologically protected edge states. The magnonic crystal is formed of dipolarly coupled Permalloy triangles. We show that due to the geometry of the block, the size of the structure can be scaled up. In addition, edge states can be found over a wide frequency range. Experimental detection of edge excitations in the considered system can be done with state-of-the-art techniques. Thus, we demonstrate a proof-of-concept magnonic Chern topological insulator nanostructure with simple geometry feasible for experimental realization. Furthermore, by tuning the strength of the perpendicular magnetic field, we induce a topological phase transition, which results in the change of direction of the topological edge state. Then, we demonstrate the magnonic switch based on this effect.
