Improving the Sensitivity of Superconductor-Based DC Magnetometer

• Published in: Journal of superconductivity and novel magnetism 2012-10, Vol.25 (7), p.2539-2545
• Main Authors: Alıkma, Fatma, Birlikseven, Cengiz, Gulmez, Gulay, Turhan, Enis, Gulce Coker, Eylem, Topal, Ugur
• Format: Article
• Language: English
• Subjects: Characterization and Evaluation of Materials; Coiling; Condensed Matter Physics; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Cuprates superconductors (high tc and insulating parent compounds); Direct current; Exact sciences and technology; Harmonics; Instruments, apparatus, components and techniques common to several branches of physics and astronomy; Magnetic components, instruments and techniques; Magnetic fields; Magnetic Materials; Magnetism; Magnetometers for magnetic field measurements; Optimization; Original Paper; Physics; Physics and Astronomy; Sensors; Strongly Correlated Systems; Superconductivity; Superconductors
• ISSN: 1557-1939; 1557-1947
• DOI: 10.1007/s10948-012-1684-0

In this study we report on some critical factors affecting the sensitivity of a magnetic field sensor whose working principle is based on a linear DC field dependence of the second harmonic of the AC response in polycrystalline type-II superconductors. DC-fields down to 2 nT in magnitude could be detected by finding optimal conditions. The optimal sensor design was determined by studying superconductor cores having different geometries and coil configurations. The optimal AC-field frequency, which is required for excitation of the specimen, was found to be 50 kHz. The second harmonic signal changes quite linearly with the DC-field up to 0.1 Oe.