Influence of dc bias currents on Co/Cu/Co nonlocal spin valves

Abstract

The spin signals of three Co/Cu/Co nonlocal spin valves have been measured as a function of a dc bias current. Both increases and decreases of spin signals have been observed. The increase in spin signal is attributed to the redistribution of the injection current at a high current density. A shift in effective injection point up to ∼100 nm is estimated. The decrease in spin signals is attributed to structural change of the materials and interfaces due to the prolonged exposure to a high-density current.