  The propagation and controlled manipulation of strongly nonlinear,
two-dimensional solitonic states in a thin, anisotropic ferromagnet are
theoretically demonstrated. It has been recently proposed that spin-polarized
currents in a nanocontact device could be used to nucleate a stationary
dissipative droplet soliton. Here, an external magnetic field is introduced to
accelerate and control the propagation of the soliton in a lossy medium.
Soliton perturbation theory corroborated by two-dimensional micromagnetic
simulations predicts several intriguing physical effects, including the
acceleration of a stationary soliton by a magnetic field gradient, the
stabilization of a stationary droplet by a uniform control field in the absence
of spin torque, and the ability to control the soliton's speed by use of a
time-varying, spatially uniform external field. Soliton propagation distances
approach 10 $\mu$m in low loss media, suggesting that droplet solitons could be
viable information carriers in future spintronic applications, analogous to
optical solitons in fiber optic communications.
