Excess velocity of magnetic domain walls close to the depinning field

Abstract

Magnetic field driven domain wall velocities in [Co/Ni] based multilayers thin films have been measured using polar magneto-optic Kerr effect microscopy. The low field results are shown to be consistent with the universal creep regime of domain wall motion, characterized by a stretched exponential growth of the velocity with the inverse of the applied field. Approaching the depinning field from below results in an unexpected excess velocity with respect to the creep law. We analyze these results using scaling theory to show that this speeding up of domain wall motion can be interpreted as due to the increase of the size of the deterministic relaxation close to the depinning transition. We propose a phenomenological model which allows to accurately fit the observed excess velocity and to obtain characteristic values for the depinning field $H_d$, the depinning temperature $T_d$, and the characteristic velocity scale $v_0$ for each sample.

References in corpus (15)

• Advances in the Physics of Magnetic Skyrmions and Perspective for Technology
• Creep and flow regimes of magnetic domain wall motion in ultrathin Pt/Co/Pt films with perpendicular anisotropy
• The 2014 Magnetism Roadmap
• Interfacial Dzyaloshinskii-Moriya interaction in perpendicularly-magnetized Pt/Co/AlO${}_x$ ultrathin films measured by Brillouin light spectroscopy
• Magnetic skyrmion-based synaptic devices
• Asymmetric magnetic bubble expansion under in-plane field in Pt/Co/Pt: effect of interface engineering
• Effect of interfacial intermixing on the Dzyaloshinskii-Moriya interaction in Pt/Co/Pt
• Dynamics below the depinning threshold
• Pinning dependent field driven domain wall dynamics and thermal scaling in an ultrathin Pt/Co/Pt magnetic film
• Creep dynamics of elastic manifolds via exact transition pathways
• Thermal rounding of the depinning transition
• Short time relaxation of a driven elastic string in a random medium
• Thermal rounding exponent of the depinning transition of an elastic string in a random medium
• Thermal rounding of the depinning transition in ultrathin Pt/Co/Pt films
• Universal non stationary dynamics at the depinning transition

Cited by in corpus (1)

• From bulk descriptions to emergent interfaces: connecting the Ginzburg-Landau and elastic line models