Structural origins of effective anisotropy in stripe domain formation
Phys. Rev. B 114, 034406 – Published 6 July, 2026
DOI: https://doi.org/10.1103/syjs-sqt5
Abstract
The origin of stripe-domain (SD) formation in soft magnetic thick films remains unresolved, particularly in NiFe-based systems where SDs are often associated with columnar microstructure. Here, by combining fixed-thickness processing control, decisive reference samples, quantitative structural and magnetic analysis, and micromagnetic validation, we show that the experimentally determined effective anisotropy is the key controlling factor for SD formation. Columnar, microstructure in NiFe films is identified as an important, but nonunique, structural route for generating or enhancing this anisotropy. A pressure-tuned 350-nm NiFe series traverses labyrinth-SD, SD, and in-plane-domain states at fixed thickness, whereas an annealed 200-nm NiFe series exhibits systematic stripe broadening without a change in thickness. These data are complemented by an amorphous FeCoHf SD film and a 130-nm-thick columnar NiFe film without SDs. These two reference samples demonstrate that columnar microstructure is neither necessary nor sufficient for SD formation. Stripe-bearing and stripe-free states are separated more clearly by the experimentally determined effective anisotropy scale than by the mere presence of columnar geometry. Within the columnar NiFe family, the aspect ratio provides a useful structural proxy for stripe stabilization, and stripe broadening is quantitatively associated with reduced effective anisotropy. Minimal micromagnetic simulations reproduce both the shift of the SD-IP phase boundary and the increase in stripe period under reduced perpendicular anisotropy. We conclude that SD formation is governed by a processing-defined effective anisotropy landscape, within which columnar microstructure is an important structural route but not a universal prerequisite for stabilization.
