Detection of a magnetic bead by hybrid nanodevices using scanning gate microscopy

• Main Authors: H. Corte-León, P. Krzysteczko, F. Marchi, J.-F. Motte, A. Manzin, H. W. Schumacher, V. Antonov, O. Kazakova
• Format: Article
• Language: English
• Published: AIP Publishing LLC 2016-05-01
• Series: AIP Advances
• Online Access: http://dx.doi.org/10.1063/1.4943147

Hybrid ferromagnetic(Py)/non-magnetic metal(Au) junctions with a width of 400 nm are studied by magnetotransport measurements, magnetic scanning gate microscopy (SGM) with a magnetic bead (MB) attached to the probe, and micromagnetic simulations. In the transverse geometry, the devices demonstrate a characteristic magnetoresistive behavior that depends on the direction of the in plane magnetic field, with minimum/maximum variation when the field is applied parallel/perpendicular to the Py wire. The SGM is performed with a NdFeB bead of 1.6 μm diameter attached to the scanning probe. Our results demonstrate that the hybrid junction can be used to detect this type of MB. A rough approximation of the sensing volume of the junction has the shape of elliptical cylinder with the volume of ∼1.51 μm3. Micromagnetic simulations coupled to a magnetotransport model including anisotropic magnetoresistance and planar Hall effects are in good agreement with the experimental findings, enabling the interpretation of the SGM images.