  We investigate the current-excited magnetization dynamics in a narrow
ferromagnetic Permalloy wire by means of Lorentz microscopy, together with the
results of simultaneous transport measurements. A detailed structural evolution
of the magnetization is presented as a function of the applied current density.
Local structural deformation, bidirectional displacement, and magnetization
reversal are found below the Curie temperature with increasing the current
density. We discuss probable mechanisms of observed features of the
current-excited magnetization dynamics.
