Influence of geometry on domain wall propagation in a mesoscopic wire

The propagation of a single magnetic Bloch domain wall (DW) in a mesoscopic wire is studied by use of the extraordinary Hall effect. Whereas a straight DW propagates freely in a wire with constant lateral width, the propagation in a Hall cross reveals that both DW shape and DW velocity vary strongly as a function of DW position. These results give the first experimental evidence that the dynamical properties of a magnetic DW in a patterned structure are strongly affected by the device geometry. This has to be taken into account for future applications to spin electronic devices.