Title
Micromagnetic Simulations of Submicron Vortex Structures for the Detection of Superparamagnetic Labels.
Abstract
We present a numerical investigation on the detection of superparamagnetic labels using a giant magnetoresistance (GMR) vortex structure. For this purpose, the Landau-Lifshitz-Gilbert equation was solved numerically applying an external z-field for the activation of the superparamagnetic label. Initially, the free layer's magnetization change due to the stray field of the label is simulated. The electric response of the GMR sensor is calculated by applying a self-consistent spin-diffusion model to the precomputed magnetization configurations. It is shown that the soft-magnetic free layer reacts on the stray field of the label by shifting the magnetic vortex orthogonally to the shift direction of the label. As a consequence, the electric potential of the GMR sensor changes significantly for label shifts parallel or antiparallel to the pinning of the fixed layer. Depending on the label size and its distance to the sensor, the GMR sensor responds, changing the electric potential from 26.6 mV to 28.3 mV.
Year
DOI
Venue
2020
10.3390/s20205819
SENSORS
Keywords
DocType
Volume
micromagnetic simulations,superparamagnetic labels,vortex structures,giant magnetoresistance,lab-on-a-chip device
Journal
20
Issue
ISSN
Citations 
20
1424-8220
0
PageRank 
References 
Authors
0.34
0
5
Name
Order
Citations
PageRank
Lukas Wetterau100.34
Claas Abert241.85
Dieter Suess311.39
Manfred Albrecht400.34
bernd witzigmann501.01