Experimental observation of the interaction of propagating spin waves with N\'eel domain walls in a Landau domain structure

摘要

The interaction of propagating dipolar spin waves with magnetic domain wallsis investigated in square-shaped microstructures patterned from the Heuslercompound Co$_2$Mn$_{0.6}$Fe$_{0.4}$Si. Using magnetic force microscopy, thereversible preparation of a Landau state with four magnetic domains separatedby N\'eel domain walls is confirmed. A local spin-wave excitation using amicrostructured antenna is realized in one of the domains. It is shown byBrillouin light scattering microscopy (BLS) that the domain structure in theremanence state has a strong influence on the spin-wave excitation andpropagation. The domain walls strongly reflect the spin waves and can be usedas spin-wave reflectors. A comparison with micromagnetic simulations shows thatthe strong reflection is due to the long-range dipolar interaction which hasimportant implications for the use of these spin waves for exerting anall-magnonic spin-transfer torque.