Real-Space Observation of Current-Driven Domain Wall Motion in Submicron Magnetic Wires

TLDR

Spintronic devices rely on the motion of magnetic domain walls (DW) and have recently been proposed as a new class of technology. The study aims to show that a DW can be driven directly by an electric current, which would greatly enhance device performance and functionality. The authors observe current‑driven DW motion in a micro‑fabricated magnetic wire with submicron width, using a well‑defined single DW. MFM imaging demonstrates that a single DW can be displaced back and forth by positive and negative pulsed currents, and its position can be precisely controlled by adjusting pulse intensity, duration, and polarity, proving the feasibility of current‑driven DW motion for spintronic devices.

Abstract

Spintronic devices, whose operation is based on the motion of a magnetic domain wall (DW), have been proposed recently. If a DW could be driven directly by flowing an electric current instead of a magnetic field, the performance and functions of such device would be drastically improved. Here we report real-space observation of the current-driven DW motion by using a well-defined single DW in a micro-fabricated magnetic wire with submicron width. Magnetic force microscopy (MFM) visualizes that a single DW introduced in the wire is displaced back and forth by positive and negative pulsed-current, respectively. We can control the DW position in the wire by tuning the intensity, the duration and the polarity of the pulsed-current. It is, thus, demonstrated that spintronic device operation by the current-driven DW motion is possible.