Spin-Orbit Torque Driven Multi-State Device for Memory Applications

We report the design, fabrication and measurement of a spin-orbit torque (SOT) driven multi-state memory. The multi-state memory is based on a 3-nm thick Ni 81 Fe 19 (Py) patterned in the shape of four intersecting ellipses (octagram). Writing is performed by injecting a charge current along one of the Pt wires, which generates a transverse pure spin current capable of switching Py between its states. Information is read through a magnetic tunnel junction (MTJ) using four-point technique.