Towards Nonvolatile Magnetic Crossbar Arrays: A Three-Dimensional-Integrated Field-Coupled Domain Wall Gate With Perpendicular Anisotropy

A novel three-dimensional (3D)-integrated domain wall gate (DWG) providing direct control of the DW propagation in a magnetic nanowire with perpendicular magnetic anisotropy is presented. The pinning of field-driven DWs in a notch is controlled by the fringing fields of a subjacent gate magnet. Depending on the state of the gate magnet, the propagating DW is either pinned in the notch or its movement is supported. Theoretical calculations of controlled DW pinning are shown. We experimentally demonstrate control of the DW motion in magnetic nanowires by other domains in a separated gate layer using magnetic force microscopy. Regarding potential applications, the 3D DWG enables storing and buffering of magnetic domains in order to control the signal flow of 3D-integrated perpendicular nanomagnetic logic. Furthermore, due to the uniformity of input, output, and gate contact, the 3D DWG can act as nonvolatile logic device in order to realize field-driven logic gates and magnetic crossbar arrays. (C) 2015 AIP Publishing LLC.