Current and field stimulated motion of domain wall in narrow permalloy stripe

TL;DR

This paper demonstrates that magnetic domain walls in niobium-permalloy stripes can be moved by electrical current pulses at low temperatures, showing significantly higher velocities than magnetic field pulses, with potential for advanced superconducting spintronic devices.

Contribution

It reveals that current pulses can efficiently move domain walls in superconducting-ferromagnetic bilayers, surpassing magnetic field-induced motion, enabling high-speed switching in superconducting spintronic applications.

Findings

Domain walls are shifted by electrical current in superconducting niobium-permalloy stripes.

Current-induced domain wall velocity exceeds that of magnetic field-induced motion by several orders of magnitude.

The effect persists at low temperatures with superconducting niobium, indicating potential for low-energy, high-speed devices.

Abstract

Of the new types of cryoelectronic devices under development, including phase shifters, giant magnetoresistance switches, diodes, transistors, and memory cells, some are based on hybrid superconductor-normal metal or superconductor-ferromagnet films. Control of these devices is realized by means of pulses of voltage, light, or magnetic field. Spin-polarized current may be used to switch low-temperature devices, as in spin-electronic devices. In the superconducting layer, the current is dissipation less, which would bring large reduction of energy consumption. We demonstrate that mag-netic domain walls in bilayer niobium-permalloy stripes are shifted by electrical current along the stripe even at low tem-perature, with the niobium in the superconducting state. The wall motion in response to current pulses is quite different from that induced by a magnetic field pulses only. The effect could be used to create a new type of sequentially switched serial devices because of very high value of the wall velocity, which excides by many orders of magnitude the velocity of the wall moved with magnetic field pulses.