Bursty magnetic friction between polycrystalline thin films with domain walls
arXiv:1906.06506 · doi:10.1103/PhysRevB.100.144408
Abstract
Two magnets in relative motion interact through their dipolar fields, making individual magnetic moments dynamically adapt to the changes in the energy landscape and bringing about collective magnetization dynamics. Some of the energy of the system is irrevocably lost through various coupling mechanisms between the spin degrees of freedom and those of the underlying lattice, resulting in magnetic friction. In this work, we use micromagnetic simulations to study magnetic friction in a system of two thin ferromagnetic films containing quenched disorder mimicking a polycrystalline structure. We observe bursts of magnetic activity resulting from repeated domain wall pinning due to the disorder and subsequent depinning triggered by the dipolar interaction between the moving films. These domain wall jumps result in strong energy dissipation peaks. We study how the properties of the polycrystalline structure such as grain size and strength of the disorder, along with the driving velocity and the width of the films, affect the magnetization dynamics, average energy dissipation as well as the statistical properties of the energy dissipation bursts.
arXiv comment10 pages, 10 figures
References in corpus (15)
- Power-law distributions in empirical data
- The design and verification of Mumax3
- Crackling Noise
- Dynamics of a ferromagnetic domain wall: avalanches, depinning transition and the Barkhausen effect
- Beyond power laws: Universality in the average avalanche shape
- Generic Dynamic Scaling in Kinetic Roughening
- Scaling exponents for Barkhausen avalanches in polycrystals and amorphous ferromagnets
- Statistics of static avalanches in a random pinning landscape
- Spatio-temporal patterns in ultra-slow domain wall creep dynamics
- Barkhausen instabilities from labyrinthine magnetic domains
- Barkhausen noise from precessional domain wall motion
- Intermittent collective dynamics of domain walls in the creep regime
- Spin excitations in a monolayer scanned by a magnetic tip
- Magnetic non-contact friction from domain wall dynamics actuated by oscillatory mechanical motion
- Moving magnets in a micromagnetic finite difference framework