Stochastic Magnetoresistance Behavior in Current-Perpendicular-to-Plane Submicron Spin Valve Pillars

We prepared giant magnetoresistance samples comprising of pseudo spin valve structures and measured the current-perpendicular-to-plane magnetoresistance (MR) with applied magnetic field along the easy and hard axes of the samples. When the magnetic field was applied along the easy axis, high and low resistance states representing magnetization parallel and anti-parallel states were observed. However, when the magnetic field was applied along the hard axis, two stochastic MR curves were obtained. The two distinct MR curves correspond to the different magnetizations reversal processes via two kinds of the magnetization orientation states, fully parallel and anti-parallel, at remanence. In our case, the two distinct magnetization reversal processes occurred randomly.