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arXiv · 1908.09875

SQUID magnetometer based on Grooved Dayem nanobridges and a flux transformer

Edoardo Trabaldo·Christoph Pfeiffer·Eric Andersson·Riccardo Arpaia·Alexei Kalaboukhov·Dag Winkler·Floriana Lombardi·Thilo Bauch
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Abstract

We report noise measurements performed on a SQUID magnetometer implementing Grooved Dayem nanobridge of YBCO as weak-links. The SQUID shows magnetic flux noise as low as 10 $\mu \Phi_0$/Hz$^{0.5}$. The magnetometer is realized by coupling the SQUID to a flux transformer with a two-level coupling scheme using a flip-chip approach. This improves the effective area of the SQUID and result in a magnetic field noise of 50 fT/Hz$^{0.5}$ at T=77 K.

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Edoardo Trabaldo, Christoph Pfeiffer, Eric Andersson, Riccardo Arpaia, Alexei Kalaboukhov, Dag Winkler, Floriana Lombardi, Thilo Bauch. 2019-08-26. SQUID magnetometer based on Grooved Dayem nanobridges and a flux transformer. https://doi.org/10.1109/tasc.2020.3004896

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