  The interaction of propagating dipolar spin waves with magnetic domain walls
is investigated in square-shaped microstructures patterned from the Heusler
compound Co$_2$Mn$_{0.6}$Fe$_{0.4}$Si. Using magnetic force microscopy, the
reversible preparation of a Landau state with four magnetic domains separated
by N\'eel domain walls is confirmed. A local spin-wave excitation using a
microstructured antenna is realized in one of the domains. It is shown by
Brillouin light scattering microscopy (BLS) that the domain structure in the
remanence state has a strong influence on the spin-wave excitation and
propagation. The domain walls strongly reflect the spin waves and can be used
as spin-wave reflectors. A comparison with micromagnetic simulations shows that
the strong reflection is due to the long-range dipolar interaction which has
important implications for the use of these spin waves for exerting an
all-magnonic spin-transfer torque.
