Figure 5
From: Noise of a superconducting magnetic flux sensor based on a proximity Josephson junction
Characterization of flux noise performance of the voltage-biased SQUIPT device. (a) DC current and (b), current noise as a function of magnetic flux at several values of bias voltage, measured simultaneously in the same setup at 60 mK. (c) Responsivity ∂I/∂Φ at several biases. (d) Flux sensitivity at the 2nd and 3rd lowest bias voltages V = 0.24 mV and 0.29 mV in panels (a –c). The dotted lines use \({S}_{{{\rm{I}}}_{{\rm{S}}}}\) obtained by direct fitting of the measured S V spectra, whereas the solid lines assume full shot noise \({S}_{{{\rm{I}}}_{{\rm{S}}}}=2e|I({\rm{\Phi }})|\) with I(Φ) from the DC measurement. Each color in panels (a)–(d) corresponds to a specific bias voltage.
