Current-Induced Two-Level Fluctuations in Pseudo-Spin-Valve (Co/Cu/Co) Nanostructures

Two-level fluctuations (TLF) in spin-valve pillars embedded in electrodeposited nanowires with the injection of a spin-polarized current were analyzed. Giant magnetoresistance (GMR) of the spin-valve system was measured at low current and hysteresis measurements were performed under large dc currents. The spin-valve acted as a two-state system defined by the two relative orientations of the magnetic layers with qualitatively different dependences on current intensity. The positive current shifted the field range over which the TLF zone was seen to more positive magnetic fields, while negative current shifted it to more negative fields.