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تسجيل مستخدم جديدMagnetic field sensing with the kinetic inductance of a high-$T_mathrm{c}$ superconductor
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We carry out an experimental feasibility study of a magnetic field sensor based on the kinetic inductance of the high-$T_mathrm{c}$ superconductor yttrium barium copper oxide. We pattern thin superconducting films into radio-frequency resonators that feature a magnetic field pick-up loop. At 77 K and for film thicknesses down to 75 nm, we observe the persistence of screening currents that modulate the loop kinetic inductance. According to the experimental results the device concept appears attractive for sensing applications in ambient magnetic field environments. We report on a device with a magnetic field sensitivity of 4 pT/Hz${}^{1/2}$, an instantaneous dynamic range of 11 $mu$T, and operability in magnetic fields up to 28 $mu$T.
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