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arXiv · 1706.05189

A new family of field-stable and highly sensitive SQUID current sensors based on sub-micrometer cross-type Josephson junctions

M. Schmelz·V. Zakosarenko·T. Schönau·S. Anders·J. Kunert·M. Meyer·H. -G. Meyer·R. Stolz
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Abstract

We report on the development of a new family of SQUID current sensors based on sub-micron cross-type Josephson tunnel junctions. Their low total junction capacitance permit high usable voltage swings of more than 100 {\mu}V and exceptional low noise of the SQUIDs at 4.2 K. Integrated rf-filter as well as high tolerable background fields during cool-down of up to 9.6 mT enable their highly reliable and easy use. With input coil inductances ranging from 10 nH to 2.8 {\mu}H and current sensitivities and coupled energy resolution down to 65 fA/Hz^{1/2} and below 10 h, respectively, they are a versatile tool for numerous applications.

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M. Schmelz, V. Zakosarenko, T. Schönau, S. Anders, J. Kunert, M. Meyer, H. -G. Meyer, R. Stolz. 2017-06-16. A new family of field-stable and highly sensitive SQUID current sensors based on sub-micrometer cross-type Josephson junctions. https://doi.org/10.1088/1361-6668/aa7216

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