{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T03:20:05Z","timestamp":1760239205492,"version":"build-2065373602"},"reference-count":50,"publisher":"MDPI AG","issue":"20","license":[{"start":{"date-parts":[[2020,10,15]],"date-time":"2020-10-15T00:00:00Z","timestamp":1602720000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>We present a numerical investigation on the detection of superparamagnetic labels using a giant magnetoresistance (GMR) vortex structure. For this purpose, the Landau\u2013Lifshitz\u2013Gilbert equation was solved numerically applying an external z-field for the activation of the superparamagnetic label. Initially, the free layer\u2019s 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.<\/jats:p>","DOI":"10.3390\/s20205819","type":"journal-article","created":{"date-parts":[[2020,10,15]],"date-time":"2020-10-15T09:02:03Z","timestamp":1602752523000},"page":"5819","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Micromagnetic Simulations of Submicron Vortex Structures for the Detection of Superparamagnetic Labels"],"prefix":"10.3390","volume":"20","author":[{"given":"Lukas","family":"Wetterau","sequence":"first","affiliation":[{"name":"Computational Electronics and Photonics and CINSaT, University of Kassel, 34121 Kassel, Germany"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4999-0311","authenticated-orcid":false,"given":"Claas","family":"Abert","sequence":"additional","affiliation":[{"name":"Physics of Functional Materials, University of Vienna, 1090 Vienna, Austria"}]},{"given":"Dieter","family":"Suess","sequence":"additional","affiliation":[{"name":"Physics of Functional Materials, University of Vienna, 1090 Vienna, Austria"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0795-8487","authenticated-orcid":false,"given":"Manfred","family":"Albrecht","sequence":"additional","affiliation":[{"name":"Institute of Physics, University of Augsburg, 86159 Augsburg, Germany"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9705-9516","authenticated-orcid":false,"given":"Bernd","family":"Witzigmann","sequence":"additional","affiliation":[{"name":"Computational Electronics and Photonics and CINSaT, University of Kassel, 34121 Kassel, Germany"}]}],"member":"1968","published-online":{"date-parts":[[2020,10,15]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"955","DOI":"10.1002\/adma.201570032","article-title":"Flexible Electronics: High-Performance Magnetic Sensorics for Printable and Flexible Electronics","volume":"27","author":"Karnaushenko","year":"2015","journal-title":"Adv. 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