Spin wave propagation in a magnonic crystal with a tailored defect

The introduction of tailored defects in a magnonic structure could lead to scenarios where the connection between fundamental physics and technological applications can develop the next generation of high frequency microwave devices. The study of magnonic crystals itself have inspired multiple investigations on the behavior of the amplitude frequency characteristic as a function of different structural parameters. However, up to now, most of the scientific reports deal exclusively with the resulting spin wave spectrum for the complete structure and little has been said about the behavior of the spin wave inside the defects. Here, we present a detailed study of the propagation and evolution of surface spin waves (MSSW) through a MC with broken translational symmetry, the influence of the defect in the spin wave propagation, the evolution of frequency bandgaps inside the MC, and the spatial energy distribution as a function of frequency and position. A time and space resolved magneto inductive probing system has been used to map the spin wave propagation in a magnonic crystal with tailored defects. The results show that the spin wave modes get trapped by the defect and the energy is localized in the space for specific frequencies.