  The interplay between electron-scale and ion-scale phenomena is of general
interest for both laboratory and space plasma physics. In this paper we
investigate the linear coupling between whistler waves and slow magnetosonic
solitons through two-fluid numerical simulations. Whistler waves can be trapped
in the presence of inhomogeneous external fields such as a density hump or hole
where they can propagate for times much longer than their characteristic time
scale, as shown by laboratory experiments and space measurements. Space
measurements have detected whistler waves also in correspondence to magnetic
holes, i.e., to density humps with magnetic field minima extending on
ion-scales. This raises the interesting question of how ion-scale structures
can couple to whistler waves. Slow magnetosonic solitons share some of the main
features of a magnetic hole. Using the ducting properties of an inhomogeneous
plasma as a guide, we present a numerical study of whistler waves that are
trapped and transported inside propagating slow magnetosonic solitons.
