The wire width is w=400 nm and is shaped into a curve to allow initialization of the DW using a globally applied field H I. Scale bars, 2 μm ( c), 400 nm ( c, inset).įigure 1c shows a scanning electron microscope (SEM) image of a fabricated device. The black arrows show the orientation of the initialization field H I and bias field H B.

The initial DW position is shown by the white arrows. ( c), SEM image of a DW-Logic device prototype, showing the magnetic wire of width w=400 nm and the MTJ under the center electrode with area 1 μm × 400 nm, also shown in the inset. ( b), Cartoon showing the DW switched to the opposite side of the device, representing bit 0. When the wire magnetization is parallel to the MTJ magnetization, the current at the OUT terminal is high, representing bit 1. The device has three terminals, IN, CLK, and OUT.

The MgO tunnel barrier is shown in yellow. Magnetization direction is also shown by the white arrows. Right-pointing magnetic moments are red and left-pointing are blue (grey represents Ta, brown Ru, and light green IrMn). ( a), Cartoon of the domain wall (DW) logic device, comprised of a magnetic wire with a DW and a magnetic tunnel junction (MTJ) to read out the DW position. These results provide a path for realizing spintronic circuits. We demonstrate that a single device can perform buffer and inverter operations, one device can drive two subsequent devices and three devices in series act as a circuit of three inverters. The device is nonvolatile and is predicted to scale to switching energies competitive with field-effect transistors 1. Information is stored in the position of a DW in a short, narrow ferromagnetic wire, written using spin-torque transfer 18 from pulsed voltage clocks, and read out using a magnetic tunnel junction (MTJ) 19. The device is a memory cell that we adapt to logic. In this work, we present magnetic device prototypes that are capable of integration in logic circuits and easily adaptable to the continuing advances in spintronics materials and scaling. However, so far, little work has shown experimentally verified DW-based devices that can perform logic, be used in circuits, and have a gate-like basic element that can be used to build more complex circuits. These devices show promise for future computing, and work has been done to simulate and build them.

Many groups are working on instantiations of magnetic logic and memory, for example, ratchet memory 12, three-terminal magnetic random access memory 13, majority logic gates 14, 15, nanomagnetic logic 16 and mLogic 17. Recent developments in perpendicular anisotropy materials 7, 8 and spin Hall effect-assisted domain wall (DW) switching 9, 10, 11 have reduced the current density required to switch a magnet. There is great interest in encoding information in magnetic materials for future memory and logic 1, 2, 3, 4, 5, 6.

Buffer gate project red