Power optimization for domain wall motion in ferromagnetic nanowires

TL;DR

This paper investigates how to optimize power consumption in moving domain walls within ferromagnetic nanowires by using resonant, time-dependent currents, potentially leading to more energy-efficient memory devices.

Contribution

It derives effective equations of motion for domain walls and proposes a resonant current method to significantly reduce Joule heating, enhancing energy efficiency.

Findings

Resonant current can reduce Joule heating in domain wall motion.

Power optimization depends on damping, spin torque, and Dzyaloshinskii-Moriya interaction.

Proposes a novel approach for energy-efficient magnetic memory devices.

Abstract

The current mediated domain-wall dynamics in a thin ferromagnetic wire is investigated. We derive the effective equations of motion of the domain wall. They are used to study the possibility to optimize the power supplied by electric current for the motion of domain walls in a nanowire. We show that a certain resonant time-dependent current moving a domain wall can significantly reduce the Joule heating in the wire, and thus it can lead to a novel proposal for the most energy efficient memory devices. We discuss how Gilbert damping, non-adiabatic spin transfer torque, and the presence of Dzyaloshinskii-Moriya interaction can effect this power optimization.