Domain wall displacement induced by subnanosecond pulsed current

We show that a single current pulse as short as 0.4 ns can trigger domain wall (DW) displacement in spin-valve stripes of 0.3 mum width inserted into a coplanar waveguide. The experiments were carried out with varying current pulse amplitude, duration, polarity, and applied static magnetic field. In zero field, DW displacement occurs in the same direction as the conduction electron current. In finite applied field, the direction of DW displacement is that favored by the field orientation. In both cases, the DW displacement occurs only above a critical current density j(c) of the order of 10(6) A/cm(2). The distance traveled by the DW along the stripe increases with the current pulse amplitude and applied field strength, but it does not depend on the pulse duration between 0.4 and 2 ns. (C) 2004 American Institute of Physics.