A theoretical investigation has been made of the nonlinear propagation
of
dust-acoustic waves in a magnetized three-component dusty plasma consisting
of a negatively
charged dust fluid, free electrons and vortex-like distributed ions. It
is found
that, owing to the departure from the Boltzmann ion distribution to a vortex-like
one, the dynamics of small- but finite-amplitude dust-acoustic waves in
a
magnetized dusty plasma is governed by the modified Korteweg–de Vries
equation.
The latter admits a stationary dust-acoustic solitary-wave solution that
has larger
amplitude, smaller width and higher propagation velocity than that involving
adiabatic ions. The effects of external magnetic field, trapped ions and
free electrons
on the properties of these dust-acoustic solitary waves are briefly discussed.