Pulsed domain wall movement was studied here in Ni80Fe20 nanowires on SiO2, using the Landau-Lifshitz-Bloch equation, including Joule heating, anisotropic magneto-resistance, and Oersted field contributions. During the applied pulse, due to the anisotropic magneto-resistance of the domain wall a dynamic heat gradient is generated. This increases the current-driven velocity by up to 15% due to the magnonic spin-Seebeck effect.

The Ni80Fe20 wire with a transverse domain wall is shown below, together with the SiO2 substrate showing the diffused heat generated by Joule heating in the wire:

The conductivity is higher at the domain wall (shown below), resulting in decreased Joule heating:

Since the domain wall is moving, the leading edge experiences a higher temperature compared to the trailing edge (see below). This temperature gradient results in increased domain wall velocity due to the magnonic spin-Seebeck effect.

S. Lepadatu, J. Appl. Phys. 120, 163908 (2016)

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