Magnetic scanning gate microscopy of a domain wall nanosensor using microparticle probe

• Published in: Journal of magnetism and magnetic materials Vol. 400; pp. 225 - 229
• Main Authors: Corte-León, H., Gribkov, B., Krzysteczko, P., Marchi, F., Motte, J.-F., Schumacher, H.W., Antonov, V., Kazakova, O.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 15.02.2016; Elsevier
• Subjects: AMR; Beads; Detection; Devices; Domain wall; Domain walls; Gates; Magnetic bead; MFM; Microscopy; Nanosensor; Nanostructure; Physics; Scanning; SGM; Magnetic bead; SGM; Domain wall; MFM; Nanosensor; AMR
• ISSN: 0304-8853; 1873-4766
• DOI: 10.1016/j.jmmm.2015.07.116

We apply the magnetic scanning gate microscopy (SGM) technique to study the interaction between a magnetic bead (MB) and a domain wall (DW) trapped in an L-shaped magnetic nanostructure. Magnetic SGM is performed using a custom-made probe, comprising a hard magnetic NdFeB bead of diameter 1.6µm attached to a standard silicon tip. The MB–DW interaction is detected by measuring changes in the electrical resistance of the device as a function of the tip position. By scanning at different heights, we create a 3D map of the MB–DW interaction and extract the sensing volume for different widths of the nanostructure's arms. It is shown that for 50nm wide devices the sensing volume is a cone of 880nm in diameter by 1.4µm in height, and reduces down to 800nm in height for 100nm devices with almost no change in its diameter. •AFM tips with a magnetic bead attached used to test interaction with domain wall.•Domain wall inside a nanostructure affect the electrical resistance.•Recording electrical resistance while scanning with modified AFM probe.•Change of resistance as a function of the position of the magnetic bead.•This allows comparing different devices in a reproducible and controllable way.