Domain Wall Injection in Spin Valve Systems with Reservoirs of Different Geometries

This study investigates nanostrips in Co/Cu/Py spin valve structures by connecting one side to domain wall reservoirs of different shapes in order to manipulate the switching field. The switching field increases according to the injection geometry; a diamond-shape reservior generates the largest switching field, followed by square-shape and then tip shape reservoirs. Simulation indicated the same results, showing that the vortex domain walls nucleated at the junction, but the pinning force increased as the magnetic transition area became larger (the injection angle became smaller). Therefore, by controlling the domain wall injection angles, the switching fields of the nanostrips can be manipulated.