Interaction of Magnetization and Heat Dynamics for Pulsed Domain Wall Movement with Joule Heating

TL;DR

This study investigates how heat and magnetization interact during pulsed domain wall movement in Ni80Fe20 nanowires, revealing that Joule heating and resistance effects significantly influence domain wall velocity and displacement efficiency.

Contribution

It introduces a comprehensive simulation approach combining thermoelectric and micromagnetic effects, highlighting the impact of Joule heating on domain wall dynamics under different pulsing conditions.

Findings

Heat gradients increase domain wall velocity by up to 15%.

Constant voltage pulses are more efficient for domain wall displacement.

Maximum displacement occurs at an optimal pulse strength.

Abstract

Pulsed domain wall movement is studied here in Ni80Fe20 nanowires on SiO2, using a fully integrated electrostatic, thermoelectric, and micromagnetics solver based on the Landau-Lifshitz-Bloch equation, including Joule heating, anisotropic magneto-resistance, and Oersted field contributions. During the applied pulse the anisotropic magneto-resistance of the domain wall generates a dynamic heat gradient which increases the current-driven velocity by up to 15%. Using a temperature-dependent conductivity significant differences are found between the constant voltage-pulsed and constant current-pulsed domain wall movement: constant voltage pulses are shown to be more efficient at displacing domain walls whilst minimizing the increase in temperature, with the total domain wall displacement achieved over a fixed pulse duration having a maximum with respect to the driving pulse strength.