2013/04/21 by R. Monaco, C. Granata, Monaco, Roberto +5
Engineering · Physics and Astronomy · #FOS: Physical sciences #Instrumentation and Detectors (physics.ins-det) #Magnetic Field Sensors Techniques #Mesoscale and Nanoscale Physics (cond-mat.mes-hall) #Physics of Superconductivity and Magnetism #Superconducting and THz Device Technology #Superconductivity (cond-mat.supr-con)
paper · pdf · doi:10.48550/arxiv.1304.5761
openalex publication_date 2013/04/21 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/28
A superconducting magnetometers based on the magnetic field dependence of the Eck step voltage in long Josephson tunnel junctions (LJTJs) is demonstrated. The field to be measured is applied perpendicular to a continuous superconducting pickup loop. Wherever the loop has a narrow constriction, the density of the flux-restoring circulating currents will become relatively high and will locally create a magnetic field large enough to bring a biased LJTJ in the flux-flow state, i.e., at a finite voltage proportional to the field strength. This method allows the realization of a novel family of robust and general-purpose superconducting devices which, despite their simplicity, function as ultra-low-noise, wide-band and high-dynamics magnetometers. The performances of low-Tc sensor prototypes, among which a highly linear voltage responsivity and a magnetic spectral density SB1/2< 3 fT/Hz1/2, promise to be competitive with those of the best superconducting quantum interference devices.