  The use of spin waves (SWs) as data carriers in spintronic and magnonic logic
devices offers operation at low power consumption, free of Joule heating.
Nevertheless, the controlled emission and propagation of SWs in magnetic
materials remains a significant challenge. Here, we propose that
skyrmion-antiskyrmion bilayers form topological charge dipoles and act as
efficient sub-100 nm SW emitters when excited by in-plane ac magnetic fields.
The propagating SWs have a preferred radiation direction, with clear dipole
signatures in their radiation pattern, suggesting that the bilayer forms a SW
antenna. Bilayers with the same topological charge radiate SWs with spiral and
antispiral spatial profiles, enlarging the class of SW patterns. We demonstrate
that the characteristics of the emitted SWs are linked to the topology of the
source, allowing for full control of the SW features, including their
amplitude, preferred direction of propagation, and wavelength.
