Imaging spin properties using spatially varying magnetic fields

We present a novel method to image spin properties of spintronic systems using the spatially confined field of a scanned micromagnetic probe, in conjunction with existing electrical or optical global spin detection schemes. It is thus applicable to all materials systems susceptible to either of those approaches. The proposed technique relies on numerical solutions to the spin diffusion equation in the presence of spatially varying fields to obtain the local spin response to the micromagnetic probe field. These solutions also provide insight into the effects of inhomogeneities on Hanle measurements.