Real time observation of the field driven periodic transformation of domain walls in Permalloy nanowires at the Larmor frequency and its first harmonic

We have observed two different field driven precessional propagation modes of a magnetic domain wall in permalloy nanowires using time resolved resistance measurements. The resistance of the nanowire oscillates at the Larmor precession frequency and at its first harmonic, corresponding to periodic transformations of the propagating domain wall between a transverse wall and either one of a vortex or an antivortex wall or both of these. © 2008 American Institute of Physics.