Micromagnetic simulations of submicron vortex structures for the detection of superparamagnetic labels
- Author(s)
- Lukas Wetterau, Claas Abert, Dieter Suess, Manfred Albrecht, Bernd Witzigmann
- 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.
- Organisation(s)
- Physics of Functional Materials
- External organisation(s)
- Universität Kassel, Universität Augsburg
- Journal
- Sensors
- Volume
- 20
- Pages
- 1-13
- No. of pages
- 13
- ISSN
- 1424-8220
- DOI
- https://doi.org/10.3390/s20205819
- Publication date
- 10-2020
- Peer reviewed
- Yes
- Austrian Fields of Science 2012
- 103018 Materials physics, 103017 Magnetism
- Keywords
- ASJC Scopus subject areas
- Analytical Chemistry, Biochemistry, Atomic and Molecular Physics, and Optics, Instrumentation, Electrical and Electronic Engineering
- Portal url
- https://ucris.univie.ac.at/portal/en/publications/micromagnetic-simulations-of-submicron-vortex-structures-for-the-detection-of-superparamagnetic-labels(12b120a5-da87-4acc-bf45-bad160b5bdf5).html