Geometrical dependence of domain-wall propagation and nucleation fields in magnetic-domain-wall sensors
Borie B, Kehlberger A, Wahrhusen J, Grimm H, Klaeui M (2017)
Publication Type: Journal article
Publication year: 2017
Journal
Book Volume: 8
Article Number: 024017
Journal Issue: 2
DOI: 10.1103/PhysRevApplied.8.024017
Abstract
We study the key domain-wall properties in segmented nanowire loop-based structures used in domain-wall-based sensors. The two reasons for device failure, namely, distribution of the domain-wall propagation field (depinning) and the nucleation field are determined with magneto-optical Kerr effect and giant-magnetoresistance (GMR) measurements for thousands of elements to obtain significant statistics. Single layers of Ni81Fe19, a complete GMR stack with Co90Fe10/Ni81Fe19 as a free layer, and a single layer of Co90Fe10 are deposited and industrially patterned to determine the influence of the shape anisotropy, the magnetocrystalline anisotropy, and the fabrication processes. We show that the propagation field is influenced only slightly by the geometry but significantly by material parameters. Simulations for a realistic wire shape yield a curling-mode type of magnetization configuration close to the nucleation field. Nonetheless, we find that the domain-wall nucleation fields can be described by a typical Stoner-Wohlfarth model related to the measured geometrical parameters of the wires and fitted by considering the process parameters. The GMR effect is subsequently measured in a substantial number of devices (3000) in order to accurately gauge the variation between devices. This measurement scheme reveals a corrected upper limit to the nucleation fields of the sensors that can be exploited for fast characterization of the working elements.
Involved external institutions
Germany (DE)How to cite
APA:
Borie, B., Kehlberger, A., Wahrhusen, J., Grimm, H., & Klaeui, M. (2017). Geometrical dependence of domain-wall propagation and nucleation fields in magnetic-domain-wall sensors. Physical Review Applied, 8(2). https://doi.org/10.1103/PhysRevApplied.8.024017
MLA:
Borie, B., et al. "Geometrical dependence of domain-wall propagation and nucleation fields in magnetic-domain-wall sensors." Physical Review Applied 8.2 (2017).
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