Spin orbit torques allow to move efficiently DW in tracks made of ferromagnetic/spin Hall effect bilayer. Domain wall (DW) detection is then of great importance. In this letter, we demonstrate a detection method, based on the ability for a ferromagnetic nanowire, in which a DW is pinned, to inject or detect a pure spin current. The device allows detecting the DW by taking advantage of the material used to generate the spin orbit torques, like Pt, and consists a ferromagnetic nanowire in contact with an orthogonal spin Hall effect (SHE) nanowire. When a current flows along the ferromagnetic nanowire, and provided a DW is pinned, the pure spin current is transformed into a transverse voltage by inverse spin Hall effect (ISHE). In the reciprocal configuration, the pure spin current created by the direct SHE, generates a transverse voltage along the ferromagnetic wire.

Electrical detection of magnetic domain walls by inverse and direct spin Hall effect
V. T. Pham, G. Zahnd, A. Marty, W. Savero Torres, M. Jamet, P. Noël, L. Vila, and J. P. Attané
Citation: Applied Physics Letters 109, 192401 (2016);