Scanning magnetic microscope based on magnetoimpedance sensor for measuring of local magnetic fields

• Published in: Journal of magnetism and magnetic materials 2020-09, Vol.510, p.166938, Article 166938
• Main Authors: Gudoshnikov, S., Tarasov, V., Liubimov, B., Odintsov, V., Venediktov, S., Nozdrin, A.
• Format: Article
• Language: English
• Subjects: Amorphous ferromagnetic microwire; Copper wire; Diameters; Ferromagnetism; Iron; Magnetoimpedance; Pickup coils; Scanning magnetic microscope; Sensors; Stray magnetic fields
• ISSN: 0304-8853; 1873-4766
• DOI: 10.1016/j.jmmm.2020.166938

•An off-diagonal magnetoimpedance sensor based on amorphous ferromagnetic microwire.•Scanning GMI magnetometer for measuring of stray magnetic fields near the sample surface.•Magnetic image of miniature current carrying structure.•Magnetic image of a sample containing micrograms magnetic nanoparticles.•Magnetic image of Fe-rich amorphous ferromagnetic microwires. A scanning magnetic microscope based on an off-diagonal magnetoimpedance sensor is presented. As a sensor, we use a 4 mm segment of glass covered microwire, having a metallic core diameter of 13.5 μm and CoFeCrSiB composition and a pick-up coil wound around the microwire containing 70 turns. The magneto-impedance sensor is fixed perpendicular to the surface of the sample, in such a way that the distance between the tip of the microwire and the sample is about 200 μm. The relative movement of the sample and the GMI sensor is carried out using a non-magnetic X-Y positioner. Measurements are taken inside the magnetic screen. For test measurements, samples in the form of the letters IWMW – of the conference abbreviation are used. The samples were made based on thin copper wire, Fe-rich amorphous ferromagnetic microwires and printed by laser-jet printer. Clear magnetic images were obtained on all samples, which demonstrates the high practical potential of the proposed method.